



m 



















Class 
Book 



TS8 50 




4. 



CQHfRIGHT DEPOSIT. 




MACHINE MOLDER 
PRACTICE 



AN INSTRUCTIVE, ILLUSTRATED MANUAL ON 

MOLDER WORK— THE OPERATION AND 

SUPERINTENDANCE OF THE 

MOLDING MACHINE 



BY 



W. H. ROHR 

PROFESSIONAL WRITER ON MACHINE 
WOOD-WORKING 



:.50 



INDIANAPOLIS 

PRACTICAL BOOKS CO. 

INDIANA 






Copyright. 1919. The Practical Books Co. 

All Rights Reserved. 

Published November 1919. 



DEC 19 1919 



.A.561027 



PEEFACE. 



Several years previous to the publishing of this book, the 
vvriter, then a practicing woodworker, was firmly convinced 
that a manual on molder practice would be welcomed by 
thousands of machine woodworkers who possess only the 
limited knowledge acquired by years of experience in a 
single or several establishments. 

Molder work involves many operations and considerable 
technique. A book which would lack any of the details or 
variety of modern methods used in air kinds of woodwork- 
ing plants would be incomplete and of limited value to the 
trade in general. 

Undoubtedly the previous absence of such a w^ork as this 
is accountable for in the fact that to produce a compre- 
hensive treatise most likely to meet the requirements of the 
greatest number of persons meant months of traveling for 
the author, and consultation with hundreds of practical 
men over the country in order to uncover and separate the 
most modern and efficient methods in use. 

Fortunately, the writer has had just such an opportunity 
to gather material for this book, henc© the knowledge dis- 
closed in the subsequent pages has been verified by personal 
observation and practical experience. 

'No attempt is made to establish in each case set rules for 
the subject treated. Unusual conditions require special 
treatment, and in numerous occasions one may, even witb 



4 MACHINE HOLDER PRACTICE. 

the aid of this book, be compelled to lean upon his owoi skill 
in solving the problems of his work. Some of the principles 
and practical details, while superfluous to the expert, are 
included, however, for the general class. 

The author desires to record in these pages special ac- 
Imowledgement of the assistance rendered him by Mr. G-. H. 
Oburn, and to machinery manufacturers who permitted the 
illustrating of their molders and equipment. Thanks, too, 
for the courtesies extended to me by friends thruout the 
United States whose suggestions and practical ideas assisted 
in making possible this, the first work on molder practice. 

W. H. ROHR. 



CONTENTS. 



CHAPTEE I. 



rii 



The Alignment of a Molder 9 

CHAPTER 11. 
Planning Set-Ups and Selecting Knives 15 

CHAPTER III. 
Balancing Molder Knives 23 

ch:apter IV. 

Setting Up a Molder. 27 

CHAPTER V. 

Making Under-Cuts and Dovetail Grooves 36 

CHAPTER VI. 

The Use of Special Guides and Forms 41 

CHAPTER VII. 
Running Molding Pace Down 55 

CHAPTER VIII. 

Special Surfacing and Milling Knives 59 

CHAPTER IX. 
Braces and Knives for Heavy Work 65 

CHAPTER X. 
Making Moldings in Multiples 75 



6 MACHINE HOLDER PRACTICE. 

CHAPTER XI. 
Miscellaneous Holder Work. 86 

CHAPTER XII. 
High-Speed Holder Work 93 

CHAPTER XIII. 
Knife Haking 122 

CHAPTER XIV. 
Babbitting High-Speed Bearings 136 

CHAPTER XV. 
Belting and Installing Holders 142 

CHAPTER XVI. 
Holding Shapes 151 



MACHINE HOLDER PRACTICE. 




CHAPTER I. 

THE ALIGNMENT OF A MOLDER. 

The four-sided molder has held an important place in 
the wood-working industry ever since wood-working ma- 
chines came into general use. Today the modern im- 
proved molder is a greatly used machine in most factories 
manufacturing wood products; in fact, it is absolutely in- 
dispensable in establishments making interior and exterior 
wood trim, fixtures, show cases, cabinets, furniture, pianos, 
picture frames, caskets, incubators, harvesting machines 
and other agricultural implements, street and railway cars, 
toys and novelties, etc. 

Altho the bulk of the v^ork done on an ordinary molding 
machine consists of moldings or molded work of different 
kinds, the machine's usefulness is not limited to this class 
of v^ork. A molder can be set up to perform such oper- 
ations as plain surfacing, gang ripping, plain milling, glue 
jointing and some kinds of irregular shaping. 

It is a most interesting machine. To operate a molder or 
to even stand near one and observe how rough stock enters 
the rolls, passes thru the machine and comes out so 
smooth and nicely molded, or milled to shape, is indeed, 
fascinating. It is this fascination that has lured many am- 
bitious and mechanically-inclined young men to choose 
molder work as their vocation. The molder appeals to the 
average young man, more so, perhaps, than any other 
wood-working machine because the work gives opportunity 
to display his mechanical ability, and it possesses enough 
variety to make it both agreeable and intensely interesting. 

There are many things to know about molder work, and 
heretofore there have been so few occasions to learn even a 
fair part of them thoroly that today there is a scarcity of 
first-class moldermen — men who can put a molder in good 



10 



MACHINE MOLDER PRACTICE. 




THE ALIGNMENT OF A HOLDER. 



11 








CO f-; 

It 

O i=i 

o o 



^ O 






03 

e a 



O M 



s -^^ 

^ rt-, s^ 

M c^ 

^ 2 fl 

"^^ 5 "^ 

o o fl 

., g ., 



w ce 
.S ft 



12 MACHINE MOLDER PRACTICE. 

order, keep it in perfect repair^ make and temper cutters, 
and set np accurate!}^ and quickly for any kind of molding 
or milled work. 

The care and operation of a molder should be learned 
thoroly, step by step, beginning first with the alignment of 
the machine. Correct machine alignment is a necessary re- 
quirement in the production of good molding. No amount 
of skill at setting up or feeding the machine will success- 
fully overcome imperfections in the line-up of the bed, 
guides, chipbreakers, feed rolls, etc. It is the imperfect 
alignment of some parts of the machine that causes a great 
deal of apparently mysterious molder trouble. Testing and 
adjusting the line-up of a molder, when necessary, is a 
comparatively simple matter if once clearly understood. A 
long and short straight edge, a steel square, and wrenches to 
make adjustments are needed before starting. 

Begin by testing and leveling up the bed. See that the 
bed plates opposite the side heads are neither too high nor 
too low, and that the rear table back of the bottom head 
lines up with the main bed lengthwise, and that crosswise it 
lines with the cutting circle of the bottom head. Level the 
lower feed rolls with the bed and let their upper faces 
come above the bed just enough to relieve the friction of 
stock as it passes over the bed under the top infeed rolls. 
The first bottom roll should be set slightly higher than the 
second to permit the stock to feed straight into the machine 
without cramping or bending. The exact amount of eleva- 
tion recommended for the lower rolls, see dotted line A in 
Fig. 1, will depend upon the kind of stock generally run, 
and whether it is surfaced or run in the rough. Ordinarily 
the second roll is given 1/32 to 1/16-in. elevation above the 
bed and the first roll is set slightly higher. 

As to the guides, those parts which form the inside guide 
or guide rail from the infeed end of the machine to the 
inside head I, are the only really permanent, stationary 
guides on a molder (all others are adjustable as occasion 



THE ALIGNMENT OF A HOLDER. 13 

requires, to the finished width of the molding) therefore, 
they must be lined with special care. When they are ad- 
justed to a perfectly straight line from end to end, and set 
square with the top head, the bolts should be set down tight 
so that no part of the guide rail can possibly shift or move 
out of position. 

By studying the line-up of the feed rolls in the plan of 
Fig. 1, it is apparent that they are not set perfectly square 
with the guide rail. A slight forward lead is given them so 
that the stock feeding thru the machine will have a ten- 
dency to always feed tightly up to the guide rail. This is 
an important detail. It assists the machine feeder won- 
derfully, especially when he has crooked lumber or short 
lengths of wide material to run. All molding machines 
do not permit of this adjustment but on the later types of 
molders the adjustment is generally possible. When the 
rolls are set in this manner it is unnecessary to put exces- 
sive tension upon the side springs, or to employ extra 
levers and devices to hold the stock up tightly to the guide 
rail. 

The top head chipbreaker C, and the side head chip- 
breaker S, should be adjusted to swing in a little past line 
with the cutting circles described by the top and outside 
heads respectively, so that both will hold the stock firmly 
in place even tho it be a little under size in places. 

It is also apparent in Fig. 1, that the inside ends of the 
top and bottom heads are set a fraction of an inch "in" 
past the line of the guide rail, and similarly the lower 
ends of both side heads fall a little below the bed line. This 
is done purposely to permit of bolting overhanging mold- 
ing cutters close to the ends of the heads, and when the 
heads are so positioned to suit the operator, they should 
be marked and not shifted from their position unless abso- 
lutely necessary. 

The side head spindles should, of course, set plumb with 
the machine bed, and the top and bottom heads should line 



14 



MACHINE MOLDER PRACTICE. 



parallel with it. If they do not, the defect should be cor- 
rected or the amount they are "out" should be carefully 
measured so that it can be taken into account when making 
set-ups or adjusting the molder gage. 

With these suggestions, any molder can be lined up cor- 
rectly, and, in the language of shop, the molderman "knows 
where he is." Operation can then begin with the assurance 
that the machine is in condition to turn out first-class 
molding insofar as alignment is concerned. 




Typical square, slotted cutterhead fitted with ordinary 
straight surfacing- knives made of carbon steel. 



CHAPTEE II. 

PLANNING SET-UPS AND SELECTINa KNIVES. 

When ready to set up a molder for any kind of work, first 
examine the drawing or sample furnished, then plan the 
set-up accordingly. The golden rule to observe is to choose 
the quickest and easiest method by which smooth, accurate 
molding can be produced with safety. The best way to han- 
dle any particular job is always governed by such local con- 
ditions as the size and kind of machine and cutters avail- 
able, amount of molding to be run, the kind and condition 
of stock, whether soft or hardwood, wet, green, semi-dry or 
kiln dried, surfaced or unsurfaced, etc. 

All stock for moldings should be thoroly kiln dried be- 
fore it is worked and all hardwoods for high-grade finish 
moldings should be surfaced before being put thru the 
molder. Softwood may be run in the rough, but if high- 
grade finish is required, it is best to have the stock planed 
first, unless it is to be manufactured into molding on a 
modern five-head or six-head molder having- straight planer 
heads at the front and molding profile heads at the rear 
end. 

An expert, when acquainted with his machine and the 
conditions which prevail where he works, can tell the in- 
stant he sees the outlines of any ordinary molding just how 
he is going to make it. A less experienced man, however, 
must give a little time to studying it out. 

Moldings are now run both face up and face down, but 
the old-established practice is to make them face up, there- 
fore the face-up method will be discussed now, and the 
face-down system explained in Chapter VII. All of the 
early four-side molders were designed to work the face side 
of molding with the top head, the edges with the side heads, 
and the back with the bottom head, and this is the way 



16 



MACHINE HOLDER PRACTICE. 



moldings are worked at the present time in a large number 
of factories. 

Another well-established practice which has been handed 
down by pioneers in the trade is to work the thick edge of 
moldings next to the guide rail, and this is usually the 
best plan even in light of modern methods, unless one has to 
run two or more different widths having exactly the same 
molded side and edge, as for example, round-edge casings, 
chair rail, apron, base, etc. In the latter case the molded 
edge should be run next to the guide rail regardless of 




Fig-. 2. 



M, wide, solid knife. S, T, R, sectional knives for 
combination set-up. 



whether it is thick or thin, so the knives will not have to be 
shifted or changed when the machine is changed to suit 
different widths of the same style of molding. With this in- 
formation it is apparent that moldings similar to the one 
shown in Fig. 2 should be run with the molded side up and 
the thick edge to the guide rail. The edge will be sur- 



PLANNING SET-UPS AND SELECTING KNIVES. 



17 



faced with the side heads and if the stock has not been 
previously planed, the back must be dressed with the bot- 
tom head. 

If a rabbett is required as indicated by dotted lines at A, 
it can be cut with knives either on the inside head or bottom 
head. A bevel, cove or quarter-round can be made at this 




Fig. 



3. Patterns with thin edges are often worked with 
the top head. 



comer in the same manner, but in most cases it is best to 
use the bottom head for such work because it is more ac- 
cessable, has greater belt power, and there is more clearance 
for the sweep of cutters. Tongu.es and grooves and certain 
other shapes, however, can only be worked on the edges with 
the side heads. When a rabbett is made in such manner 
that a very thin edge is left on the molding, as at B, Fig. 2, 
the rabbett should be worked with the side head instead of 
the bottom head. Otherwise, the thin remaining edge 
would probably be broken off, or at least, badly chipped 
and split away in places. 

When a pattern tapers down to a comparatively thin edge 
as at J, K, L and 0, Fig. 3, it is generally better to leave 
the outside head idle, or both side heads if both edges are 
thin, and finish the edge as well as the face of the molding 
with the top head, provided the stock is not more than 
1%-in. thick. It is usually dangerous to cut down thru 
stock thicker than IVg-i^- with ordinary cutters. 



18 MACHINE HOLDER PRACTICE. 

Double beveled edges like those on crown moldings, see 
Fig. 4, are made with knives on the top and bottom heads 
whenever possible — rarely with the side heads. However, 
when making patterns like this the outside head (carrying 
straight knives) is used to size the stock to a uniform width 
so that it will advance properly between close-fitting guides 
to the bottom head, where the final cut is made. Compara- 
tively thin moldings, 13/16-in. or less, are often sized to 
width with a pair of sizing knives on the top head. 

A point worth remembering in planning, work ahead at 
the molder is the possibility of saving time and labor by 
grouping the work according to its kind and size. Hard- 
wood moldings and those containing deep, heavy cuts are 
run at slow feeds and often with special cutters, therefore 
these should be grouped whenever possible. Likewise there 
can be a grouping of widths and thicknesses and patterns of 
the same profile. This always helps to materially reduce 
the amount of vs^ork necessary in changing a machine from 
one pattern to another. 

SELECTING KNIVES. 

The types of molding knives commonly used on square 
heads consist of slotted knives, see M and E, Fig 2; spike 
knives, S and T, Fig. 2; milled-to-pattern slotted knives, 
X, Fig. 5 ; thin high-speed steel knives under caps, Y and 
Z, Fig. 5. Wide slotted laiives, made of either solid or 
laid carbon steel, are the old-fashioned type and are still 
used in many plants. At one time it was the universal 
custom to make a pair of wide knives for each pattern of 
molding, but this slow, expensive practice has been largely 
superseded by what modern moldermen call the combina- 
tion set-up in which several narrow knives are combined to 
make any required cut. The latter is by far the better 
method to use when a large variety of moldings are manu- 
factured, and it is often the best on stock work. Some of 
the chief reasons why the wide solid knives have been 



PLANNING SET-UPS AND SELECTING KNIVES. 



19 



abandoned are, because they are expensive in first cost, diffi- 
cult to make, and when once made they are hard to keep in 
shape and sharpen. Each wide knife is only good for one 
pattern of molding. Take the knife M, Fig. 2, for ex- 
ample ; it cannot be used to make any other pattern, hence 




Fig. 4. Showing- how sectional cutters should be arranged. 

its usefulness is very limited. It contains two corners 
which can be reached only with a three-cornered file, thus 
necessitating a filing temper which will not hold a sharp 
edge very long. In the process of resharpening, this knife 
will gradually wear wider between the corners that are 
filed, and in doing so it loses its original shape. If a small 
nick developes at any point, the entire edge must be re- 
ground and filed in order to preserve the same general 
profile. 

N"arrow knives, on the other hand, are less expensive in 
first cost, easier to make, and can be so designed that all in- 
side corners are eliminated, thus permitting the entire edge 
to be sharpened on a grinding wheel. This feature allows 
using a harder temper, which holds a keen edge longer, and 
makes it possible to keep the knives in correct shape in- 



20 MACHINE HOLDER PRACTICE. 

definitely. Narrow knives also have the important ad- 
vantage of being readily adapted id a wide range of work 
on a variety of patterns. Another point in their favor is 
that by breaking up a wide, complicated cut with several 
narrow knives (see S, T and E, Fig. 2, and A, B, C, D, etc., 
Fig. 4)' distributed around on different sides of the head, 
there is less strain on the bolts and a better balanced and 
an easier-running cutting unit is provided. The result is a 
smoother finish and less chipping of the grain. 

A large assortment of narrow knives is extremely valu- 
able in plants manufacturing odd and special work be- 
cause the same knives can be used repeatedly in different 
combinations to cut all sizes and shapes of molding. New 
patterns can be worked and obsolete ones frequently 
matched without making or changing a cutter. The neces- 
sary combinations are simply built up with the knives at 
hand. Narrow knives should be grouped in the racks ac- 
cording to shape and size. An assortment for general work 
will include a large variety of quarter and half-rounds, 
coves, beads, ogees, reverse ogees, bevels, surf acers, gi'ooving 
and rabbetting cutters., quirks, etc. 

Spike knives like S and T, Fig 2, are made from long 
bars of carbon or self -hardening steel, 1^4 to 5/16-in. thick. 
Often they are spread at the end to make a wider cut. They 
are fastened to the head under square steel caps or washers 
about 14-in. thick, see Fig. 7, Chapter IV. Two spikes 
must be placed under a plain cap like that in Fig. 7, but 
caps can be made with one edge bent over or offset in such 
a manner that the shoulder will take the place of the slug 
shown in Fig. 7. Caps of the latter type are especially good 
for side heads where there is seldom any call for more than 
one molding knife on each side of the head. . 

Milled knives like X, Fig. 5, may be purchased from 
stock or made in the grinding room on a modern head- 
grinding machine. The profile of the mold is milled in 
the back, and a face bevel is ground on the front as show^n. 



PLANNII^G SET-UPS AND SELECTING KNIVES 21 




Fig. 5. X is milled knife with front bevel. Y and Z show thin 
steel knives under* caps. 



22 MACHINE HOLDER PEACTICE. 

The knife is sharpened by grinding the flat face-bevel. In 
some cases a strip of high-speed steel is brazed onto the 
front beveled face, as shown by dotted lines at X, Fig. 5, 
in order to give a harder and longer-lasting cutting edge. 
The advantages of milled knives are that they retain their 
correct shape until worn out, are easily sharpened, produce 
very smooth work on kiln-dried stock, and never tear out 
cross grain. On the other hand, their usefulness is limited 
to comparatively light cuts and considerable more power is 
required to drive them thru the stock. Knives of this type 
are used in a great many mills in the Pacific Northwest 
for working bone-dry fir. 

The cutter shown at Y, in Fig. 5 consists of an ordinary 
slotted knife, milled as shown, to receive a narrow strip of 
high-speed steel. The chief purpose of this kind of combi- 
nation is to utilize thin-steel knives that are worn too nar- 
row for further use as surfacing knives. The narrow cut- 
ters are particularly adapted to making beads and V's on 
beaded and V-ceiling, also other light, narrow cuts of a 
similar nature. 

Still another method of using thin high-speed steel on 
square slotted heads is shown at Z. High-speed steel cut- 
ters will hold an edge for a long time and are quite satis- 
factory for relatively light cuts. They are often made 
from broken planer, matcher or jointer knives, altho in 
some plants, regular high-speed bar steel is purchased for 
making small molding and spike knives. Unlike carbon 
steel, high-speed steel requires no heat treatment before 
using. 



CHAPTEE III. 

BALANOIN-Q HOLDER KNIVES. 

Correct knife balance is one of the most important fac- 
tors in molder work. Every molderman who expects to 
produce high-grade molding and keep his machine in good 
running order, with the least amount of trouble and ex- 
pense, should exercise particular care and good judgment 
in balancing the cutters. 

It is a well-known mechanical axiom that any object re- 
volving at high speed must be in a perfect state of balance 
to proceed smoothly and safely without vibration. This is 
especially true of the cutterheads on molding machines, as 
they run from 3,000 to 4,000 r.p.m., and any slight devia- 
tion from a perfect running balance produces a violent jar, 
causing the bearings to heat, hence a wavy finish on the sur- 
face of the molding. There are at least four kinds of bal- 
ance that must be observed when balancing a set of knives : 
dead-weight, line, projection and thickness balance. Theo- 
retically, the knives on opposite sides of a cutterhead should 
pair exactly in dead-weight, in thickness and in projection, 
and they should be in perfect line directly opposite one an- 
other on the head. It is quite possible to keep straight 
dressing knives and some molding knives in this theoreti- 
cally ideal alignment, but w^hen using sectional knives it 
is more often impossible and even undesirable to always 
have them paired in this manner. 

In actual practice, especially in factories turning out odd 
detail work where frequently twenty or more set-ups are 
made in a day on a machine, there is seldom, if ever, more 
than one knife used for each member of the molding. As a 
result, a knife that cuts one member is balanced by one that 
cuts another member, or by a "dead" knife bolted opposite 



24 



MACHINE HOLDER PRACTICE. 



to it. Eight here it might be well to explain that on short 
runs there is no advantage in bolting a pair of knives 
shaped exactly alike onto opposite sides of the heads with 
the expectation that both knives will cut alike and conse- 
quently produce smoother work than one, because it is 



1 ' 1 1 1 'I r"— T — r—^ 1 r"— 1 — r- H 


1 
1 




_. , . 1 




1 

G 1 

1 

^_:: 1 . 


H 






4 
^ 


T. ,-1 ■■■■■ 

1 










1 




V* 





Fig-. 6. G, knives set in staggered fashion. H and I, correcting 
staggered effect. 

practically impossible to set two knives to cut alike. They 
can be made to cut alike by jointing at full speed or by re- 
peatedly whetting the knife that sets out the farthest, but 
this is only profitable on long runs. 

To successfully balance sectional knives one must strive 
to become an expert at balancing, which he can do by using 
good judgment and observing the tried-and-tested rules of 
knife balance. Perfection in balancing is only acquired by 
experience, but the following rules w^ill serve as a valuable 
guide: 



BALANCING HOLDER KNIVES. 25 

Eule 1. When necessary to mate two knives, one of 
which mnst be set out farther than the other, the knife 
projecting the farthest should be the lightest in dead 
weight. Any deficiency in weight in the short knife can be 
made np by nsing an extra washer or heavier bolt, or by 
slipping a slug of metal in the bolt slot under the short 
knife. It is always a good plan to keep a number of wash- 
ers and weight slugs of different sizes on hand for use in 
forcing a balance in emergencies. The same methods are 
followed to produce a balance when one knife is thicker or 
heavier than its mate. 

Eule 2. The center of weight of a pair of knives, bolted 
to opposite sides of a cutterhead, should come exactly in 
line. In other words, no pair of knives should be set in 
staggered fashion as shown at G, Fig. 6. In practice this 
rule cannot always be followed to the letter, so the next 
best thing under adverse conditions is to observe Eule 3. 

Eule 3. The center of weight of a group of knives, bolted 
to opposite sides of the head, must come absolutely in line 
to maintain the running balance of the cutterhead. This 
latter rule is a hard and fast one — there is pio getting 
around it. However, it permits setting a pair of knives in 
staggered fashion on condition that suitable weights or an 
extra knife or set of knives, as required, are so placed as to 
counteract the staggered effect and bring the center of 
weight on opposite sides of the head in line, see H, Fig. 6. 
One more method to counteract the effect of staggered 
knives appears at I, Fig. 6. 

Eule 4. Still another point in knife balance that should 
be observed when using sectional cutters is to distribute the 
cutting knives around the head as evenly as possible. In 
other words, do not bolt all the knives on one side of the 
head and the balance weights on the other side. Likewise, 
do not bolt all the knives that cut heaviest on one side, and 
those that cut lightest on the other side if it can be avoided. 
Furthermore, when running a many-membered molding. 



26 



MACHINE MOLDEE PRACTICE. 



avoid putting both knives, which cut at or near; the outer 
edges of the molding, on the same side of the head. Let 
one edge-knife come on one side of the head while the other 
comes on the opposite side of the head. These last points 
are clearly illustrated in Fig. 4, Chapter II. Here the top 
bevel knives A and D are not placed on the same side of 
the head, neither are the bottom bevels E and F. Knives 
A and C on one side of the head are balanced by B and D, 
respectively, on the opposite side, while the knife that cuts 
the middle part is balanced by a mate of the same shape 
or by any knife of the right weight that comes handy. 
Bevels E and F are balanced with similar bevels of the same 
general shape and weight, or by any available knives of the 
required weight. 




Thin, high-speed steel surfacing knives attached to square 
head with caps and bolts. 



CHAPTEE IV. 

SETTING UP A HOLDER. 

Setting the knives and adjusting the machine for a run 
of new molding are tasks that test a molderman's skill 
and ability. It is therefore to his interest to have things 
handy about the machine and to practice a method of set- 
ting up that is at once simple, accurate and rapid. The 
common mistake of some operators is to proceed witln the 
execution of their work with no well-defined or systematic 
method, and as a result, they make a number of false moves 
and do more or less unnecessary tinkering at the machine 
every time they set it up. These useless moves consume 
valuable time and reduce efficiency. Even by the best 
methods there are several adjustments to make v^hen set- 
ting up for new work or changing from one job to another, 
therefore it is apparent that a predetermined and efficient 
system is very essential. 

The first requisite for convenience in setting up is to 
have a variety of wood pressure bars grouped together in 
a rack near the machine. The necessary machine wrenches 
and a long-handled screw driver should also have their 
appointed places within easy reach. Extra knife bolts 
with washers and nuts, screws for the pressure bars, ham- 
mer, pliers, bevel and try-square, oil-slip, wiping waste 
and a few clean blank templets should be. kept in a drav^er 
near at hand. 

The machine should be fitted with index plates and 
pointers to show at a glance just how far to set the top 
head from the bed of the machine to cut a given thickness 
and how far to set the outside head from the guide rail 
to cut a given width. There should also be marks to indi- 
cate the location of the bottom and inside heads for differ- 
ent size cuts. It requires an extra move and additional time 



28 MACHINE HOLDER PRACTICE. 

to measure machine adjustments with a rule and the 
chances for inaccuracy are much greater. It is not safe to 
determine these distances by counting the turns made with 
the crank or hand wheel because machine screw threads 
develop play in time, and when a screw is reversed it some- 
times requires half a tutn or more before the head will 
move. 

If the feed is not under perfect control and cannot be 
stopped instantaneously with the feed lever, a simple quick- 
acting brake of home-made construction should be added 
for this purpose. It is also helpful, if quick machine stops 
are desired, to add a brake to the machine countershaft 
because the natural momentum of any smooth-running 
molder will often cause the cutterheads to continue in mo- 
tion for some time after the power has been turned off. 
The blower pipes connected to the hoods should be arranged 
to telescope or swing out of the way in such a manner that 
they will not have to be replaced every time the operator 
changes or sets the knives on a head. 

To proceed in setting up be sure to have all knives, etc., 
selected, balanced, and laid out carefully before you be- 
gin to put them on the heads. Then make it a point to 
set each head complete as you go; for example, start with 
the top head, and follow in regular order to the.. outside 
head, inside head and finally the bottom head. By adopt- 
ing and adhering to a systematic routine of this sort the 
work soon becomes easy and natural, and, one's movements 
get to be automatic, so to speak, resulting in remarkable 
speed and accuracy. 

There are a number of methods used and exploited for 
positioning or setting knives on square cutterheads, but 
the majority of uptodate moldermen thru out the coun- 
try use the molder rule in some form for this purpose. 
Molder rules made of metal or celluloid can be bought for 
a nominal price, but if one prefers he can make a rule, be- 
ing careful, however, to leave off all patented features of 



SETTING UP A HOLDER. 



29 



iniles now on the market. The ordinary molding rnle is 
lined off in %-in. divisions both ways, see Fig. 7, but the 
eighths by which the projection or overhang of the knives 
is measured are longer than true %-in. divisions. The 
reason for this is that a molder knife bolted to a square 




Fig. 7. Method of using molder or "stickerm^an's" rule. A is in 

line with guide rail. B' is in line with inside head. 

S is surfacing line. 

cutterhead strikes the work and does its cutting at an angle 
which varies according to the size of the head and amount 
of knife projection. 

Eeferring to Fig. 7, line S, on the rule, is the surfacing 
line to which the cutting edge of the straight surfacing 
knives is set. The edge of the rule rests against the lip of 



30 MACHINE HOLDER PRACTICE. 

the head, and surfacing line S is scribed parallel to, and 
about 3/32-in., or %-in. from this edge. A knife edge or 
point set up to the next line above the surfacing line will 
cut exactly %-in. deep, and if set to the second line above 
and parallel to line S, it will cut 14-in. deep, etc. Lines 
running lengthwise of the rule and parallel to line S are 
spaced to represent the molder scale, while those crossing 
them are spaced exactly %-in. apart. Line A indicates the 
position of the guide rail, and the distance from line A to B 
shows the amount allowed for the cut of the inside head, 
therefore the width and location of cuts to be made by 
knives on the top head are measured from line B unless 
the inside edge of the molding requires no surfacing, in 
which event the cuts must be measured from line A. The 
method of using the rule in actual practice is shown clearly 
in Fig. 7. The working edge of the rule always rests 
against the lip of the head while the end is either butted 
against a convenient journal-box casting as shown or ar- 
ranged to hook over the end of the cutterhead as indicated 
by dotted line. The former method is recommended when 
the construction of the machine permits its use, because 
when the rule rests against an immovable casting, the head 
can be shifted laterally either way by the adjusting wheel 
without moving the rule, consequently any lateral shifting 
does not destroy the alignment of line A with the guide rail 
nor line B with the inside head. On the other hand, if the 
rule is hooked over the end of the head the relative position 
of the head must always remain the same. . If shifted, the 
rule will also move and then require readjustment every 
time to keep it in correct alignment with the guide rail. 

One of these molder rules can be arranged to serve for 
all four heads on a machine if so desired, but it is much 
easier and more satisfactory to use a shorter rule for the 
side heads. The principle of using the rule on any of 
the other heads is the same as described for the top head. 
Some moldermen, instead of using a rule similar to that in 



SETTING UP A HOLDER. 31 

Fig. 7, use a blank rule having only the lines S, A and B. 
On this blank they locate the important points of any 
required knife profile by using an ordinary rule and a sep- 
arate molder scale. The molder scale in such cases is 
sometimes lined off on a minature brass T-square which is 
just long enough to span the width of the blank rule. 
Sometimes the scale is marked off on one edge of a regular 
two-foot, four-fold rule. Others lay off knife projections by 
measuring with a common rule and making proper allow- 
ance for the sweep of the knives. The latter method, 
however, is rather a hit-and-miss one, serving the purpose 
fairly well but not recommended. 

Another way to set molder knives, and one that is used 
successfully by some very fast set-up men, is to make a 
tracing of the molding upon transparent paper and then 
fold and fasten this tracing in the proper position on a 
blank molder rule, as shown in Fig. 8. Line L K is draw^n 
thru the deepest cut and parallel to the face of the mold- 
ing. The depth of this cut is measured and then laid off 
on the rule according to the molding scale as at L-1 and 
K-1. The tracing is then clamped to the rule so that line 
L-K comes exactly over line L-1, K-1, and the thick edge 
of the molding comes exactly in line v\^ith the inside head 
cut as shown. Now the knife edge that cuts the deepest 
member will come right over the line K-1, L-1, as shown, 
while the edge that cuts the flat surface comes only to the 
surfacing line S on the blank rule. The remaining profile 
of the molding knife falls below the tracing in proportion 
to the difference between the actual measurement and the 
molder scale, as shown in Fig. 8. 

A beginner on the molder would probably not have much 
success with this method, but an expert who has a good eye 
for shapes and can tell at a glance the exact allowance to 
make between the profile of a molding and the correspond- 
ing profile of the knife edge to cut the molding, will find 
that this gives just the guide needed for setting knives 



32 MACHINE HOLDER PRACTICE. 

quickly and accurately. The method to use, of course, is 
largely a matter of choice and the success of any particular 
system will depend altogether upon the man who uses it. 
The method just described may not appeal to some because 
it is not generally known to the trade. However, molder- 
men in some detail interior trim factories are making re- 
markable speed with it, and prefer this system to any other. 

As mentioned at the beginning of this chapter, the 
methods of knife setting described in the foregoing apply 
particularly to new moldings which the operator has never 
run. For stock moldings and repetition work it is not 
necessary to go thru the process of locating the required 
position of the knives on a molder rule after the first set- 
up has been made, provided that set-up has been properly 
"carded," or traced off on blank templets and filed away for 
future use. Templets are undoubtedly the best and quick- 
est for setting up a machine to make moldings which are 
run repeatedly. The kind of templet recommended is 
simply a blank rule made of light-colored wood or celluloid 
and, like the molder rule, is arranged to either butt against 
a journal box casting as in Fig. 7, or hook over the end of 
the head as in Fig. 8. After an original set-up is made 
correctly with a molder rule, the outline and position of the 
knives as they set on the head are then carefully traced on 
the templet with a sharp pencil. The size, name and num- 
ber of the molding are marked on the templet or set of 
templets, if more than one are necessary for a set-up, and 
these are filed away in regular order in a rack or drawer. 
It is a good plan to shellac wood templets after they are 
marked as the shellac preserves the sharp, clear-cut lines 
and keeps the templets clean. 

When all knives are positioned on the heads, the chip- 
breakers at the top and outside heads must be adjusted to 
swing-in close to the point where the knives leave the work. 
There must be a safe clearance, of course, so the tip of the 
chipbreaker will not strike the points of the knives or 



SETTING UP A HOLDER. 



33 



swing into the cutting circle when any over-size stock en- 
ters the machine. Before a piece is started into the ma- 
chine the outer guides and springs are pulled out to clear 
it and generally the blower hoods are left off for the trial 
start. The selection of the first piece of material to run 



- Ll — 




HEAD 



Fig. 8. Another method of setting knives correctly. 

is very important. It should be full size, fiat^ and perfect- 
ly straight on one edge. The straight edge is placed next 
to the guide rail. This piece is fed in slowly and carefully 
to the top head and past it a few inches, after which the ma- 
chine is stopped so that a wood pressure bar can be fitted 
to the machine pressure shoes and as closely as possible to 
the cutting circle of the top head. Some moldermen fit 
the pressure bar to the pressure shoes before starting their 



34 MACHINE HOLDER PRACTICE. 

machine but this is somewhat risky because the end of the 
bar must be high enough to clear the advancing molding 
and at the same time be close up to the top head knives. 
The least miscalculation or even the vibration of the ma- 
chine may cause the knives to catch the suspended bar and 
draw it into the head or hurl it back at the operator, thus 
causing a serious accident. This danger is not so great, 
of course, when running flat work. The pressure bar 
should be at least one-half to two-thirds the width of the 
molding and its underside should be smooth and shaped 
to conform to the general contour of the molding so that it 
will perform its function of holding the stock down firmly 
to the machine bed without marring the finished surface in 
any v^ay. 

With the pressure bar fitted into place and screwed down 
lightly, the molding is fed past the side heads, after which 
the side guides and rear end of the pressure bar are ad- 
justed. The molding is then fed over the bottom head, 
after which the tail board and the remaining guides are 
adjusted. For the reason that considerable adjusting is 
necessary while the first piece advances thru the machine, 
it is best to use a piece of cheap scrap wood for the trial 
set-up in order to avoid spoiling any good material. Even 
after all the knives are set correctly the molding will often 
fail to come exactly true to pattern until the pressure bar 
and all guides and the tail board back of the bottom head 
are adjusted and secured firmly in position. 

In all cases it is important to have the throat space or gap 
at the cutter heads as small as possible so the chips will be 
broken off close and so the stock can neither spring up, 
down, or sideways. The pressure bar and guides must not 
be set too tight, however, or the stock will not feed freely. 
When the molded end of the trial piece is sticking out at 
the rear of the molder it should be compared to the sample 
or drawing to make sure it is correct in size and shape. If 
the machine has been put in proper alignment, the molder- 



SETTING UP A MOLDEE. 35 

man has kept in mind the relative position of the heads 
with the machine bed and guides, and the molder rule has 
been adjusted correctly and the set-up made faithfully as 
recommended in this chapter, the molding will be right at 
the first trial. Otherwise, more' or less adjusting may be 
necessary to make it right. Here, let it be emphasized, is 
where time is lost and troubles begin if any preliminary 
work has been slighted. 

After the set-up is proved correct, the blower hoods are 
then put in place, the feed regulated if necessary and the 
machine oiled. The operator can then proceed to feed ma- 
terial into the machine. In feeding, be careful to observe 
the direction of the grain and look out for defects in the 
stock. The best side must be used to make the face side of 
molding and the grain should always be favored if possible, 
so the knives cutting the face of the molding will, not be 
working against the grain. Each piece of stock that is. fed 
into the machine should be butted squarely against the 
piece preceding it and the stock should be kept moving 
forward while the machine is in motion. The rate of 
feed must, of course, be regulated according to the size of 
the cut and the kind of stock being run. Generally speak- 
ing, hardv^oods require a slow or medium feed while soft- 
woods may be run at a faster rate. In taking heavy cuts 
the feed should be slower than when taking light cuts. One 
must rely largely upon his own judgment in this matter. 
When a large hard knot or burly place is approaching the 
knives, slow down the feed with the lever until the hard 
place has passed the cutterheads. The yokes, carrying cut- 
terheads, must be securely locked in place so the heads can- 
not shift or quiver while the machine is in operation. The 
tension on the top feed rolls should only be sufficient to 
carry the stock freely thru the machine, because excess ten- 
sion is hard on the feed mechanism. Experience, naturally 
acquaints the operator with numerous other little precau- 
tions to take while operating a molder. 



CHAPTEE Y. 

MAKING UNDER-CUTS AND DOVETAIL GROOVES. 

The cutting of moldings which have members that can 
only be reached by nnder-cntting presents a different and 
sometimes more difficult problem than is ever encountered 
in making ordinary straight-molded cuts. Under-cutting 
would be almost impossible without special attachments if 
it were not for the adjustment on modern molders which 
permits tilting the side heads to any angle up to about 45 
degrees. 

By working a pattern face up and cutting all of the top 
profile that can possibly be reached with knives on the top 
head, an under-cut member can usually be reached with a 
long, slender knife bolted to the outside head when the 
latter is tilted to the proper angle. For example, in Fig. 
9, the combined cornice and picture molding is worked face 
up, the top side being almost finished, excepting the under- 
cut, before it reaches the side head, see A, Fig. 9. This 
leaves only a very light under-cut to be finished with a 
knife K on the outside head which must be tilted over to the 
angle shown. When a molding is worked in this manner 
the wood pressure bar must be partly cut away just opposite 
the outside head in order to give room for the swing of the 
long, overhanging side-head cutter K. The moldings D 
and E in Fig. 10, which form the sliding frames of one 
kind of adjustable window screen, are worked in the same 
manner as just described, the small under-cuts, C C, being 
made with a knife bolted to the outside head, which is tilt- 
ed as required. 

The small under-cut part of window sills. Fig. 11, for 
special water-tight frames can be cut in this manner also, 
provided the sills are not too wide. A very long, slender 
knife is required to reach point C on the sill. If an under- 



MAKING UNDER-CUTS AND DOVETAIL GROOVES. 



37 



cut of this kind cannot be reached with an overhanging 
knife on a tilted sidehead on account of the construction of 
the machine, the usual alternative is to make all cuts ex- 



nG.9 



FIG. 10 




FIG. 13 



7 I 



FIG. 14 



E_5 



FIG. 15 



Figs. 9, 10, 11, 12, 13, 14 and 15 show different kinds of moldings 
with under-cuts. 



38 MACHINE MOLDER PRACTICE. 

cepting C on the molder and then do the under-cutting on a 
shaper. 

In running the greenhouse sash pattern, Fig. 12, in one 
operation thru a molder, it is necessary to tilt both side 
heads to make the inclined channels, C C. In case the in- 
side head will not tilt enough to make this cut, and, if there 
is only a comparatively small amount to run, the material 
can be put thru the machine twice in order to cut both side 
channels with the tilted outside head. If the latter method 
is followed, the top and outside heads should be the only 
ones in action during the first run. The top head should 
carry surfacing knives to lightly dress the top surface, thus 
making the stock uniform in thickness so that a pressure 
bar can be used to hold it firmly in place while passing the 
outside head. Knives on the outside head should be set to 
surface the side and mill the inclined channel C. They 
will, of course, remain unchanged during both runs. On 
the last run the top part of the molding must be finished 
with the top head and the bottom part with the bottom 
head. 

In an emergency, this particular pattern. Fig. 12, can be 
run without tilting or even using the side heads. To do 
this the stock should first be surfaced on one side and one 
edge and then run in a trough as shown in Fig. 13. Two 
runs are required and all cutting must be done with the 
top head. In place of the regular feed rolls, spur wheels 
should be used and positioned on the feed shaft to engage 
the stock just where the deep cuts come, i. e., at points 
B and C, Fig. 13. 

There are many other kinds of under-cuts such as 
dovetailed "ways" in table slides, dovetailed grooves in 
Byrkit lath, dovetailed staves, etc., which can be run on a 
molder. However, work of this kind is generally turned 
out in large quantities by factories especially equipped for 
it. Special attachments and sometimes entire machines of 
exclusive design are built to manufacture such work. 



MAKING UNDEK-CUTS AND DOVETAIL GROOVES. 



39 



There are table-slide machines which make such patterns 
as Fig. 14 and Fig. 15^ complete in one operation. One 
particular machine has, in addition to the four ordinary 
heads, a pair of overhead tilting arbors mounted near the 
rear in such manner that they can be fitted with cutters to 
under-cut the corners of a square-edge groove worked by 
the top head and make a dovetailed groove of it, as in Fig. 
14. Anofher machine has overhead vertical spindles, the 




Fig-. 16. Attachment for working Byrkit (dovetail) lath, at rear 
end of an inside molder. 

ends of which are fitted with dovetailed router bits to cut 
pattern Fig. 14, or the ends can be fitted with small milling 
cutters to make the slot in pattern Fig. 15. 

In factories where production is sufficient to justify the 
expense, special attachments are used which fit on or in 
line with an ordinary molding machine. For instance, in 
making Byrkit lath some mills use a portable stand fitted 
with tilting spindles which carry either saws or cutter- 



40 MACHINE HOLDER PRACTICE. 

heads, and when the occasion demands it this stand is 
placed in line with the rear of the machine to make the un- 
der-cuts after the straight grooves have been milled with the 
top or bottom heads. One of the^e lath-making attach- 
ments is shown lined up at the rear on an inside molder 
in Fig. 16. 

An ingenious device for making dovetailed grooves on 
one edge of a certain pattern consists of a small horizontal 
spindle attachment mounted just back of the outside head. 
The end of this spindle carries a dovetail routing bit so 
positioned that it lines up exactly with a square groove 
worked in the stock with straight knives on the outside 
head. Therefore, when the machine is in operation the 
dovetail router bit finishes the inner corners of the groove 
cut by the outside head, and makes a perfect dovetail, 
groove. The spindle attachment has a pulley which is 
belted to the machine countershaft. 



CHAPTEE VI. 

THE ,USE OF SPECIAL GUIDES AND FORMS. 

There are a number of different styles and kinds of mold- 
ing which, to rnn thru a molder successfully, require spe- 
cial guides and forms to hold the material in place as it 
passes thru the machine. One pattern of molding and the 
forms required for running it has already been shown in 
Fig, 13, Chapter V. Other patterns requiring the use of 
forms include wood-split pulley bushings, tapered column 
staves, piano fall boards, sprung crown molding for circle 
work, circular church seating, etc. Ordinary small mold- 
ings are sometimes run in a simple wood form, when made 
on large machines, because the form holds the thin narrow 
strips in place and prevents them from buckling and break- 
ing while passing thru the machine. 

The manufacture of v^ood-split bushings requires absolute 
accuracy and for that reason it is always advisable to make 
them in at least two operations instead of one. There is a 
choice of two different methods however, one being to work 
the stock into a perfect half-round first and mill the chan- 
nel last, while the other is just the reserve. In doing the 
work by the former method, the stock should first be faced 
off perfectly flat on one side and the two corners should be 
slabbed off on a saw or molder in order to lighten the finish 
cut. Then set up the top head with heavy divided knives 
as shown in Fig. 17, being careful that the extreme ends 
E, E of the knives are comparatively wide in proportion so 
there will be no possibility of them chattering or breaking 
in the cut. Fig. 17 shows the knives on only one side of 
the head, a quarter-round knife being to the right and a 
sizing knife S to the left. On the opposite side of the head 
the relative position of the knives is reversed, therefore it is 
important that the quarter-round knife on one side be 



42 



MACHINE HOLDER PRACTICE. 



made to balance the sizing knife S on the other side and 
vice versa. It may be necessary to use a narrovi^ false guide 
of vrood next to the guide rail in order to swing such wide- 
edged knives but this can easily be arranged if conditions 
demand it. Should the knives have a very long reach it is 
advisable to reinforce them v^ith knife braces. Chapter 
IX explains and illustrates the use of knife braces. 

The half-rounds when finished are run in a half-round 
form, see F, Fig. 18, in order to cut the channel for the 
shafting. The form F is iron or hardwood, lubricated on 
the inside with parafine or grease, and it extends from the 
in-feed end of the machine to a point some distance beyond 
the top head. It must fit the half-round molding accurate- 
ly and be securely bolted to the bed of the machine. The 
friction between the half-round material and this form F is 




Fig-. 17. Knives on one side of head for working- heavy, half- 
round molding-. Fig. 18. Form F and spur wheel A, for feeding 
half-rounds to make pulley bushings. 

naturally great, so great in fact that smooth feed rolls will 
not feed the material along. Sharp corrugated rolls or 
spur wheels like A, Fig. 18, should be used and there must 
be plenty of weight or spring pressure employed in feed- 
ing. The wood pressure bar back of the top head must be 
adjusted to work as close as possible to the cutting knives 



THE USE OE SPECIAL GUIDES AND FORMS. 



43 



and it must be set down fairly tight to prevent the finished 
bushings from chattering as they leave the machine. This 
is a very particular piece of work and accuracy is the thing 
to keep in mind. The least variation in the thickness of 




Fig. 19. Trough or form, thru which piano fallboards are fed 
to top head. 

the finished bushings or their shape will render them worth- 
less. When running half-round bushings by the other 
method, that of cutting the channel first, there is one ad- 
vantage gained. While the channel is being worked with 
the top head the outside corners of the stock can be slabbed 
off with the bottom head, thus saving one operation. On 
the second run, when the outside surface is being worked, 
the stock is run on top of a half-round form or "saddle'^ 
which fits the channel perfectly. This form is firmly fast- 
ened to the bed of the molder and lined up with the top 
head knives. 

Sometimes pulley bushings are run in quarters. The 
stock is ripped into squares and then run in a V-trough, 



44 MACHINE HOLDER PRACTICE. 

the top head cutting the channel and square edges^ and the 
bottom head cutting the convex side. It is difficult to get 
an absolutely uniform thickness by cutting one side with 
the top head and the other side with the bottom head but 
a slight inaccuracy in quartered bushings does not cause as 
much harm as in half-round bushings. 

Molding the back and front fall boards of pianos is also 
a particular piece of work and one that requires the use of 




Fig. 20. Cross -section of front fallboard. 

a trough for the first run and a "saddle" for the second run. 
Fig. 19 shows the cross section of a back fall board in the 
proper V-trough for the first run thru the machine. 

Dotted lines indicate the manner in which the stock is 
built up and glued before being worked. The top head is 
set up with a pair of heavy solid knives to cut the entire 
concave surface. As a rule the concave cut is the only one 
made during the first run because these boards are generally 
veneered on the concave surface and along the flat surface 
A B. Side A B is sometimes veneered before the stock is 
built up. The concave surface is veneered immediately 
after the boards are run thru the molder. The molded 
hinge rabbett M is worked on either the molder or shaper. 
After the fall boards are veneered bevel B D is cut either 



THE USE OF SPECIAL GUIDES AND FORMS. 45 

on a shaper or on the molder. When cut on a molder the 
fall board is run on a saddle or form having a convex sur- 
face to fit the concave side. A pair of bevel knives are 
bolted on the top head to do the cutting. 

Fig. 20 shows a typical front fall board which is general- 
ly run in practically the same manner as described for back 
fall boards. When the board is to be veneered the molded 
beads., B, B are left off and a molded strip is glued to the 
surface afterward. In case the front fall board is finished 
from the solid wood it is completely cut on the molder in 
two runs with the exception of the under corner C which 
is worked afterward on a shaper. Corrugated feed rolls 
or spur v^heels like A, Fig. 18, should be used on the feed 
shaft when work of this kind is run. It is best to use a 
pair of spur wheels for the second run and position them 
on the feed shaft so they straddle the hump of the fall 
board. The saddles or forms over which fall boards and 
such work are run are made of solid wood, molded accurate- 
ly to proper shape and bolted securely to the machine bed. 
The saddle should line up parallel with the guide rail and 
should extend well past the top head so the pressure bar 
can be used to good advantage. 

Tapered staves for tapered wood-stave columns are often 
run on ordinary molders, altho there are special molders 
with moving side heads guided by cams for this purpose, 
see Fig. 21. There are different methods of running tap- 
ered, staves but forms are required in every case, unless a 
special machine or attachment is employed, and the forms 
must pass thru the machine with the staves. In order to 
keep the staves moving thru the machine continuously there 
should be three sets of forms so that while one form is in 
the machine the helper is taking one out and passing it 
back, and the feeder is starting another into the machine. 

If only plain bevel-edged staves are required they can be 
completed in one operation by using sets of forms like those 
shown in Fig. 22. There are no lugs on these forms as the 



46 



MACHINE HOLDER PRACTICE. 




THE USE OF SPECIAL GUIDES AND FORMS. 47 

points of a few sharp nails sticking thru them give suf- 
ficient grip on each stave to prevent any slippage. When 
staves are run in this manner the material should first be 
surfaced to uniform thickness, since the top head is idle 
during the tapering process. Only the side heads are used 
and they are fitted with knives wide enough to cut the full 
thickness of a set of forms containing a stave. 

In ru.nning tapered staves on which a tongue and groove 
joint, or any other style of joint, with the exception of the 



SIDE VIEW 



Fig. 22. One method of making- plain tapered staves in one 
operation. 

plain joint mentioned, is required, the staves are put 
thru the molder tAvice, working only one edge each time. 
Fig. 33 shows a simple plan for laying out' staves and ob- 
taining correct bevels. One must plan to use lumber thick 
enough for the work and always locate the tongue and 
groove joint, or whatever style of joint is used, as near 
as possible to the inner side of the staves so that when the 
columns are turned the turning tool will not cut into the 
irregular part of the joint. The number of staves to use 
in a column will depend largely upon the size of the 
columns and the thickness of the lumber available. The 
stock for making staves may be either rough or surfaced 
and ripped either straight or tapered, but it must be cut to 
an even length. If the stock is surfaced to an absolutely 
uniform thickness the top head need not be used. Other- 
wise it must be used on the first run to bring all staves to 
the same thickness. Always run staves with the narrow or 
inner side to the top and work the beveled edge of tapered 
staves with the outside head. The side head need not be 
tilted unless the profile of the joint requires it. If the 



48 



MACHINE MOLDED PRACTICE. 



stock for staves is not ripped to a taper, the staves may be 
run the first time without tapered forms. Simply run 
the tongue edge without taper but to correct bevel. Then 
with a set of forms corresponding to the thickness, length 




Fig. 23. Showing how staves for tapered columns are laid out. 

and taper of finished staves, see Fig. 24, put the stock 
thru for the final run, this time cutting a groove to fit 
the tongue. During this final run the top head need not 
be used but the pressure bar should be set down moder- 
ately tight to hold the staves firmly to the bed of the ma- 
chine as they pass the side head. On the other hand, if 



THE USE OF SPECIAL GUIDES AND FORMS. 49 

the stave stock is ripped to a taper then tapered forms must 
be used for both runs. The forms should each have a lug 
at the end^ see L, Fig. 24, or sharp nail points along the 
edge next to the stave in order to prevent any slippage 
while passing thru the machine. At the beginning of 
the final run the staves should be tried for correct bevel 
just as soon as enough are finished to make a column. 
Accuracy is very important in stave work as the slightest 
deviation in bevel amounts to considerable when multiplied 
by the number of staves required to make a complete 
column. 

When straight staves are run on a molder both side 
heads and the top head are used and one run thru the 



MACHINE GUIDE RAIL " | 



TAPERED FORM 



STAVE 



Fig-. 24. Stave in position along-side tapered form. 

molder completes the job. In this work, when the first 
good stave is thru the machine there should be enough 
short sections cut from it to make a complete circle of the 
required column. The slightest inaccuracy can then be de- 
tected and corrected in time to avoid any spoiled work. 
When the correct bevel and joint are obtained a set of 
short sections should be assembled into a complete circle 
and tied securely with a string. This will serve as con- 
vincing evidence that the staves fit perfectly and it should 
be kept by the molderman until after the staves have been 
glued up. 

Sprung crown or cornice molding for circular porches, 
towers, etc., is another kind of work which ^t first sight ap- 
pears difiicult, if not impossible to make on an ordinary 
molder, but in reality it is very simple when proper forms 



50 



MACHINE HOLDER PRACTICE. 



are used. The fact that this kind of molding sets at an an- 
gle and is sprung around a circle makes it necessary to treat 
it as a narrow flat strip bent around a large cone. There- 




Fig. 25. Method of laying out sprung crown molding for cornice 
of circular porch or tower. 

fore, it must be sawed to a certain radius to make it line 
up level and fit properly when sprung into place around 
the circle. The method of finding the correct radius for 
sawing the stock appears in Fig. 25. The back of the 



THE USE OF SPECIAL GUIDES AND FORMS. 51 

molding (the pitch line) is simply continued until it 
strikes a line dropped from the center of the circle and the 
distance from this intersection to the farthest edge of the 
molding is the radius which must be used in sawing out 
the stock, see Fig. 25. 

In Fig. 26, A, B and C, respectively, are shown three 
ways to run flat circular work such as that just described. 
In each case the edge is run against a circular form or 
guide of wood which is clamped solidly to the machine bed. 
It will be observed that in both illustrations, A and B, Fig. 
26, the inside of the circle is run next to the form, the only 
difference in the two being that at A the form is next to 
the guide rail while at B it is on the outside. This dif- 
ference is immaterial, either method may be used to suit 
one's convenience since the principle is the same in each. 
Both methods are recommended and whenever possible 
either A or B method should be used in preference to that 
shown at C. The reason why A and B are preferred is 
because the feed rolls can be used to good advantage in 
getting the material thru the machine if the circle is not 
too small in radius. The action of the rolls at A and B 
tends to crowd the material up tightly to the form as it 
feeds thru, whereas at C just the reverse is the case. 
In attempting to feed circle work by method C the rolls 
carry it straight forv^ard and away from the form. How- 
ever, method C is sometimes the only alternative, as in the 
case of very wide material such as circular church seating, 
etc. It is frequently necessary when running a few wide 
pieces to the guide as shown at C, to raise the rolls and feed 
the work by hand. 

When running flat circular work of this kind the top 
head is usually the only one used altho sometimes one 
of the side heads can be brought into action if necessary. 
In making crown molding like Fig. 25, the material is put 
thru the machine twice, the bevels on the back being 
worked the flrst time and the face the last time. Circle 



52 



MACHINE MOLDER PRACTICE. 




\ TO CENTER OF RADIUS / 




Fig. 26. Arrangement of guides for running circle work. 



THE USE OF SPECIAL GUIDES AND FORMS. 



53 



work can also be made on edge, that is, the concave or 
convex side or edge molded with the top head by the use of 
proper forms, see Fig. 27. This class of work is really 
shaper work and is seldom run on a molder except in 
emergencies. 

In a certain large car shop the segment heads for street 
car windows are run on a small sash sticker in forms as 




Fig-. 27. Molding segment and circle work on edge. 

shown at A, Fig. 27. The sticker is used especially for 
this work and instead of having regulation square heads it 
is fitted with circular, milled, 4-wing cutters which retain 
their correct shape until worn out. These cutters do not 
chip or tear the surface of the stock when running against 
the grain on the last half of each piece. Both feed rolls 
are arranged to bear on the edge of the stock so that a con- 
tinuous pov^er feed is maintained. 

When running heavy work over circular forms it is fre- 



54 



MACHINE MOLDER PRACTICE. 



quently necessary to remove one or both top feed rolls and 
feed the stock by hand, especially if the circle is of small 
radius. One must always be guided in such emergencies 
by his own good judgment as no hard and fast rules are 
applicable. 





-■ 




1 


t 






1 

/ 




'•«sfe 


" 





A square, self-centering- side head fitted with thin steel knives 
which are clamped in place with caps and bolts. 



CHAPTEE VII. 

RUNNING MOLDING FACE DOWN. 

Early types of molding machines were designed to make 
molding face up, evidently because this seemed to be the 
only proper way to run it. Bottom heads, therefore, were 
made smaller than top heads, and driven by lighter belts 
and smaller pulleys. The overhanging part of the machine 
bed which carried the bottom head was none too 'well sup- 
ported. In those days probably no one thought of running 
molding upside down, and if he had attempted to do it with 
the machines then in use he would more than likely have 
made a complete failure. The bottom heads v^ere too light 
and did not have sufficient belt power; there was not 
enough room to accommodate the swing of large knives, 
and being mounted at the extreme end of a long overhang- 
ing bed, the bottom head would have produced wave marks 
on the face of the molding if heavy cutting had been at- 
tempted. Some primitive types of molders are still in 
service, and needless to say, it is out of the question to try 
to do anything but very light work with the bottom heads. 

Modern molding machines, however, are built differ- 
ently. The bottom heads are equal to the top heads in size 
and power, and the space around them is adjustable to per- 
mit the swing of reasonably long knives. They are amply 
supported in a massive machine frame. Thet bed plate at 
the rear swings down instead of sideways, thus giving 
convenient access to the knives. It is an easy matter to run 
molding face down on the later machines ; in fact, practical 
moldermen have learned that in many cases much better 
results are obtained by practicing the face-down method. 

Numerous arguments abound in favor of running ordi- 
nary molding face down, but probably the chief reason re- 
sponsible for a general adoption of the face-down practice 
is the increased cost of lumber and the consequent tendency 



56 



MACHINE HOLDER PRACTICE. 



of saw mills to saw more closely, scanting the lumber gen- 
erally instead of sawing full thickness. Shrinkage, due to 
kiln-drying, leaves the stock even thinner, hence when it 
is ready to be manufactured into molding a large percent 
of it is likely to be considerably scant of standard thickness. 




Fig. 28. K is roughing cutter on side head. W, X, Y, 2 are 
combination of cutters for working mold M. B is wood block 
which supports overhanging edge E. Pig. 29. M is picture 
mold being worked face down. B is supporting block. 

For example, suppose 4/4 stock is to be used for molding 
which finishes 25/32-in. ; if run face up it must measure 
about 15/16-in. in thickness or rough spots will appear on 
the face of the molding; if run face down, however, it can 
be scant %-^^' thick and still make perfect molding. The 
face-down method, therefore, is often the means of pre- 
venting the loss of an immense amount of good lumber 
on account of the scant thickness. 

Another decided advantage in the face-down process.. 



RUNNING MOLDING FACE DOWN. 57 

which is especially noticeable when making molding from 
unsurfaced lumber is that the bottom head almost invari- 
ably produces smoother work than the top head. This is 
due to the fact that the bottom head always takes a cut 
of uniform depth regardless of the varying thickness of the 
rough sawed stocky and because it is far removed from the 
infeed rolls and top chipbreaker. The bottom head also 
produces more accurate work as a rule, because when the 
stock reaches it the material is leveled off and sized to uni- 
form thickness and width, and closely confined between side 
guides and under the pressure bar. 

When moldings are run face down, practically all formed 
pressure bars are dispensed with. Only a few plain flat 
bars of different widths to suit the various widths of mold- 
ing are needed. If a small chip or part of a knot lodges 
under the pressure bar and scores the molding, no harm 
is done because the damage is on the back, whereas, if the 
molding is run face up the least scratch on the top surface 
may ruin it. It often happens that several hundred feet 
of molding are run before the operator discovers that the 
surface is being scored and, of course, if it is being worked 
face up this amount is spoiled. 

There is an additional convenience in setting up a bottom 
head for new molding and checking the correctness of the 
set-up because, when the pressure bar is set down properly, 
one can feed the first piece a few inches over the bottom 
head and quickly determine its degree of correctness with- 
out removing it from the machine. If edge-cutters or split- 
ters, which cut entirely through the molding are employed, 
they can be used to greater advantage on the bottom head 
than on the top head because there is no danger of cutting 
into iron if they are set out a fraction of an inch too far. 

Here is one more point worthy of mention. When feed- 
ing anything but the very smallest moldings, if the last 
end of a piece passes the infeed rolls v^ithout another 
closely butted against it, an ugly mark is usually made 



58 MACHINE HOLDER PRACTICE. 

across its top surface by the top head. This end is there- 
fore spoiled if the face side of the molding is at the top, 
but if it is on the bottom, no damage is done. 

In Fig. 28 there is illustrated another advantage in the 
face-down method which may be taken into account when 
any molding requires extra heavy cuts along one or both 
face corners. These cuts are often difficult and dangerous 
to make with single knives on one head, but by running the 
material face down, the heavy cuts can be divided between 
knives on the side and bottom head. For instance, in Fig. 
28, a plain bevel knife K on the side head cuts away more 
than half of the surplus wood and leaves only a compara- 
tively light cut for the finishing knives W, X, Y, Z on the 
bottom head. This is a more safe and easy way to run 
large moldings of this type and it is a method which in- 
variably produces a smoother-finished product. There is so 
much of the under side of this molding cut away, however, 
that only a very narrow part N rests on the bed as it leaves 
the bottom head. Therefore, the last end of each piece is 
likely to "cave into the knives" as the cut is completed. This 
is prevented by a block B which acts as a support for the 
overhanging edge E. In fact, suitable blocking should 
always be used, as illustrated at B, Fig. 28, and B, Fig. 29, 
to aid in supporting moldings which are under-cut to such 
an extent that they are apt to "cave in" or "roll" as they 
leave the bottom head. The adjusting of what blocking is 
required does not consume much time — not nearly so much 
as would otherwise be taken up in making, keeping in order 
and adjusting formed pressure bars for top-head work. The 
blocks are short and easily attached temporarily to the rear 
bed or side guides by wood screws. 

There are, of course, some moldings which cannot be run 
face down and others which, altho they can be run face 
down, work to better advantage face up. In doubtful cases 
one must use his best judgment in choosing the safest, easi- 
est and most practical method. 



CHAPTEE VIII. 

SPECIAL SURFACING AND MILLING KNIVES. 

When comparatively straight-grained lumber is manufac- 
tured into moldings, special knives and other devices are 
not required. But in working curly or cross-grained stock, 
or in making a groove or rabbett without planing off the 
flat surfaces adjoining it, there is need for something more 
than regular cutters and ordinary methods of knife setting 
to produce smooth work. 

One of the most general methods employed to obtain a 
smooth finish when working curly or cross-grained wood is 
to back bevel the knives as shown at B, Fig. 30. A knife 
ground in this manner makes a scraping, non-tearing cut 
instead of "picking up" and tearing out the grain. More 
power is required, however, to drive it thru the wood 
and the method can only be used successfully on thoroly 
kiln-dried lumber. Equally as good results can be obtained 
by reversing the knives on the head (the knives being 
turned upside down) but this is only recommeded in emerg- 
encies and on short runs because knives running in this 
manner are necessarily limited to light cuts on account of 
the added power required to drive them thru the stock. 

Another method of preventing torn grain in flat work is 
to set ordinary knives so they have about half the usual pro- 
jection past the lip of the head, say a scant 1/16-in. if that 
is sufficient to give clearance for the bolt heads. Should 
there be insufficient clearance when the knives are set so 
close, or, if the lip of the head is nicked and in bad con- 
dition, the same effect can be obtained by placing a piece of 
thin, flat steel (part of a resaw blade will do) under the 
knives as shown at C, Fig. 30. The piece of steel must 
be slotted like the knife and its working' edge ground per- 
fectly straight. This edge is set back only 3/64-in. or 



60 MACHINE HOLDER PRACTICE. 

1/16-in. from the cutting edge of the knife and therefore 
serves as a close-up chipbreaker, producing very smooth 
work. Instead of using a thin piece of steel under the 
knife as a chipbreaker, the knife edge may be ground as 
shown at D, Fig. 30. Altho it is a rather difficult task 
to grind this kind of cutting edge on long knives^ it is a 
simple matter to grind short straight knives this way if 
a modern head grinder is available. The latter method of 
grinding knives is used in some Pacific Coast mills and is 
claimed to be better than back beveling because the knives 
can be employed successfully for working either kiln-dried 
or air-seasoned stock. It is also claimed that a knife ground 
in this manner does not pull as hard as a back-beveled 
knife. Still another method of preventing torn grain on 




Fig. 30. Three methods of fitting- up knives for planing without 
tearing cross-grain, 

flat work is to break the cut into narrow sections by grind- 
ing a series of notches in each pair of knives, and setting 
the knives on the head so the notches mis-match in stag- 
gered fashion as shown in Fig. 31. This method is usually 
the best for heavy cuts. 

In milling square grooves and rabbetts the chief diffi- 
culty lies in making smooth sharp corners v^ithout tearing 
out the grain. A method sometimes used, but which is 



SPECIAL SURFACING AND MILLING KNIVES. 



61 



really a trick of the trade, is to set the knives so that thej^ 
cut a very slight bevel instead of cutting squarely down as 
they should cut, see Fig. 32. The amount of bevel is very 
small, about 1/32-in. or less in %-in. On cheap or hid- 
den work, this trick is scarcely ever detected but such prac- 




Fig. 31. Another way to fit up surfacing- knives for 
working cross-grain. 

tice is not recommended on first-class work. A better way 
to prevent torn grain along the face corner of rabbetts and 
grooves is to grind a small sharp spur, see S, Fig. 33, on 
the corner of the knife. This spur cuts slightly ahead of 
the main part of the knife and when properly ground works 
very satisfactory. The small crease left by the spur on 
the inside corner of the rabbett or groove is, however, an 
objectionable feature in some classes of work. 

Probably the best method of cutting smooth clean rab- 
betts in high-grade hardwood is to use a combination 
of two knives, one for cutting the edge and the other for 
cutting the face of the rabbett. An ordinary plain knife 



62 



MACHINE HOLDER PRACTICE. 



cuts the face of the rabbett, see S to T, Fig. 33, and a spe- 
cial knife like Fig. 34 or 35 cuts the edge of the rabbett 
as E to S, Fig. 33. The knife shown in Fig. 34 is really 
an ordinary beveled knife turned upside down on the head 



FIG. 33 



FIG. 32 




Figs. 32 and 33. 



Methods of fitting up rabbetting knives to 
make non-tearing cut. 



but the side clearance is reversed. Use is made of a side 
spur, S A, and only a very slight side clearance C, just 
enough to prevent the back of the knife from striking the 
edge of the rabbett. The knife is set so spur, S A, cuts pre- 
cisely the depth of the rabbett. One might think that the 
point S of the spur does the entire edge cutting but this is 
not the case. The cutting edge extends from point S to 
point A, Fig. 34, and it produces a non-tearing, slicing cut. 
The knife shown in Fig. 35, with its knife-like curved edge, 
is forged to shape and ground to make a slicing cut similar 
to that just described. It is shown in the form of a spike 
bit, but can be made slotted if desired. Great care is re- 
quired in setting either of these special edge-cutting knives, 
but once a knife of either type is properly sharpened and set, 
it will cut a perfectly smooth square edge without tearing, 
regardless of the grain or kind of wood being worked. 

Knives for cutting grooves should be made and used in 
pairs of rights and lefts, that is, one to cut one side of the 



SPECIAL SURFACING AND MILLING KNIVES. 60 

groove and its mate to cut the other side, so that as the side 
edges of the knives wear away by repeated sharpening they 
can still be set ont to cut the standard width grooves for 
which they are intended. Instead of using grooving knives 
with side spurs, as shown in Fig. 33, one can, if he prefers, 
obtain equally as good results with knives which have a 
shear-cutting bevel on the front. The knives are paired 
and positioned on the head so the sharp, shear-cutting edge 
is turned to the outside to make the edge cut. 

In Fig. 36 is shown an excellent cutter for milling nar- 
row grooves. There should be a pair of these cutters, and 




Fig-s. 34 and 35. Special knives for cutting the edge of rabbetts. 

the saw teeth instead of being filed square across at the 
front should be given a slight lead or bevel toward the 
outer edge, which is to the left for one cutter and to the 
right for the other. This produces a double shear cut. The 
front teeth of each cutter are lower than the back teeth so 
that they will not do most of the cutting when a fast rate 
of feed is carried. Cutters of this type stay sharp a long 



64 



MACHINE HOLDER PRACTICE. 



time and cut a remarkably smooth clean groove in any kind 
of wood at fast feed. They will even produce a smooth 
groove on surfaced stock v^ithout the usual "skinning off"' 
of the face side. In fact, the first cutters of this type ever 
made were designed to meet just such an emergency. The 
cutters are made of ordinary slotted steel blanks which are 
first cut at A, Fig. 36, then heated a cherry red and benfc 




Fig. 36. Special grooving cutter. 

as shown. The bent upright part of the cutter is scribed 
and roughly ground to the cutting circle of the head, after 
which the teeth are formed, jointed and sharpened. 

Grooves and rabbetts are often cut with thick saws, built- 
up thin saws, wabble saws, Shimer heads, and various high- 
speed cutterheads mounted on the proper spindles of the 
molder, and while these are all excellent methods they are 
in most instances only profitable on long runs of standard 
patterns. In many cases some of these latter methods can 
be used with good results for making various irregular- 
shaped moldings when unusually cross or curly-grained 
stock is encountered. 



CHAPTEE IX. 

BRACES AND KNIVES FOR HEAVY WORK. 

When making large moldings which require deep heavy 
cuts with long knives^ the need of braces or reinforcing de- 
vices, and sometimes special knives, immediately becomes 
apparent. The use of extra large knives is dreaded by some 
moldermen because of the possible danger involved, but if 
the knives are properly made, accurately balanced, bolted 
and braced in a substantial manner, there is scarcely any 
danger of having a "smash up." By properly made, it is 
meant that they should be made of good steel, somewhat 
thicker than the ordinary knife steel, and that the cutting 
edges should only be hardened a short distance back, thus 
leaving the main body of the knife tough rather than hard 
and brittle. A very hard knife is almost sure to break in a 
deep or heavy cut no matter how well it is braced. 

In designing or selecting a knife brace one must always 
bear in mind that the chief object of bracing is to prevent 
the overhanging end of the knife from bending back or 
shearing its bolts. Another thing to consider when select- 
ing braces and planning a set-up for heavy work is the 
amount of molding to be run, whether it is a standard pat- 
tern or just a special job which may never be called for 
again. It is neither wise nor profitable to spend a great 
deal of time fitting up something elaborate for one small 
job, and it is equally unwise and often dangerous to fit up 
a temporary makeshift for running stock patterns which 
are repeatedly ordered in comparatively large quantities. 
Practically every job of heavy molding presents problems 
peculiar to itself, but with the assistance of the following 
illustrations of devices and descriptions of their uses, any 
molderman should be able to quickly solve the difficulties 
that may arise and turn out the most complex kinds of 
molding with ease and safety. 



66 



MACHINE HOLDER PRACTICE. 



Often times the only kind of reinforcement a knife re- 
quires is an additional bolt at each side. For example, 
if a single slotted knife, say 3-in. or more in width, is set to 
take a medium heavy cut the strain of cutting is likely to 
be more than one bolt can hold, but, if a bolt is added to 
each side as shown at A, Fig. 37, thus making three in all, 
the knife can be safely held in place. The holding power 




Fig. 



Reinforcing a wide knife with bolt at each side. 



of the side bolts S, S, Fig. 37, can be further strengthened 
if a very short slot is made in each side of the knife to re- 
ceive about half or three-quarters of each bolt. Another 
good practice is to remove the bolt washers and substitute 
in their stead a soft steel plate as pictured at B, Fig. 37. 
This plate is drilled to receive the three bolts and when in 
position it spans the entire knife, thereby serving the dual 
purpose of clamping cap and bolt washer. 

Long, overhanging knives require bracing at points be- 
yond the lip of the head and reasonably close to their cut- 



BRACES AND KNIVES FOR HEAVY WORK. 



7 



ting edges. Some very effective braces for long knives are 
shown at C, D, E and F, Fig. 38, and at G and H, Fig. 39. 
The braces C, J), E and F, are simply different types of side 
braces, all being made of steel. Each brace has a mate 
to balance it. It is also a good plan to have right and left 




Fig. 38. Four different kinds of side braces. 

side braces so that knives can be braced on both sides if 
necessary. The brace C is made of ordinary slotted steel 
and arranged to hook over the lip of the head and rest in 
position alongside the knife it reinforces. Braces D and 
E are also designed to hook over the side of a knife. They 
are bolted to the side of the head immediately in front of 
the knife which they brace. The brace F is similar to D 
and E except that it is bent around at one end to fit into 



68 



MACHINE HOLDER PRACTICE. 



the bolt slot as shown and therefore does not require any 
bolts. The three braces D, E and F, are each offset, as 
illustrated, to clear the lip of the head and bring the 
"anchor point" near the cutting edge of the knife. 

When the shape of a long knife is such that it cannot be 
braced along the sides with braces as shown in Fig. 38, an 




Fig. 39. Two ways to brace extra long knives. 

eifective method of anchoring it is to drill a hole near the 
middle of the projecting part and insert a long bent bolt 
as indicated at G, Fig. 39, or an eye bolt as shown at H, 
Fig. 39. The type of anchor bolt chosen should always be 
used with a mate of the same kind, size and weight in order 
to make a good running balance when the machine is set 
up. 

As a further safety precaution it is well to have closed 



BRACES AND KNIVES FOE HEAVY WOEK. 



69 



slots in all extra long knives, see K, Fig. 39. A knife with 
a closed slot has greater strength at the back where it is 
bolted to the head. It cannot spread at the slot nor get 
away during service without stripping its bolts. These 
extra long knives should also be bent slightly forward, as 




Fig. 40. Four types of "scoop" or "loop" knives for making gutter. 

shown at K, to give the cutting edge a more acute cutting 
angle because, when bent forward, they cut more easily, re- 
quire less power, and consequently cause less strain on the 
bolts and braces. 

While the type of knife illustrated at K, Fig. 39, will 
serve fairly well for making deep cuts, the so-called scoop 
or loop knives (four different kinds of which are pictured 
in Fig. 40) are far superior in every way. The cutting 
edges of knives A, B, C and D, Fig. 40, are the same but the 
manner in which the different types of knives are bolted 
to the head differs. These knives are made of good bar 
steel and their cutting parts are bent to make the shape 
desired. Proper allowance is naturally made for clearance 
in each case. Knives of this kind will cut thru solid 
wood with remarkable ease and produce real smooth work. 
The shavings and air pass right thru the loop of the 
knives, hence there is much less resistance offered to their 



70 



MACHINE HOLDER PRACTICE. 



motion and less power is required to drive them. This 
means an added element of safety which is important. 

The knife A, Fig. 40, has two cutting* edges and is de- 
signed to slip onto a cutterhead spindle. A pair of the 
knives should be used, one with the ends bent to the right. 




Fig 



loop knife with T-bolt and steel block 



the other with ends bent to the left, and the cutters should 
be separated by spacing-collars and clamped in position 
on a spindle in the same manner that a saw is fastened to 
its arbor. One thing is certain about knives of this type, 
they cannot get away after being properly clamped onto a 
spindle. This is a point in their favor but, on the other 
hand, when they are used no other knife can be positioned 
with them on account of the absence of a cutterhead. 

Knives B, C and D, are made in pairs and designed to 
bolt directly onto any ordinary square-slotted head. Knife 



BEACES AND KNIVES FOE HEAVY WOEK. 



71 



C is made of bar steel which is thicker but narrower than 
the steel used for making types A, B and D. The cutting 
part is heated and hammered thinner and wider when the 




Fig. 42. Another method of clamping- loop knives to a square 
cutterhead. 

knife is made. Knife C possesses a marked advantage over 
the other three types of scoop knives because it is adjust- 
ahle for depth of cut. Fig. 41 shows one method of bolting 
and bracing a knife like C, Pig. 40, but a better method 
appears illustrated in Fig. 42. Usually the lips on two 
corners of the head are filed down level with the sides of 



72 



MACHINE HOLDER PRACTICE. 



the head to accommodate a pair of knives that are put on 
in this way, but it is not absolutely necessary to do this 
since the two sides of the head can be blocked up with plates, 
as shown, to make them come level with the edges of the 
lips. This method of positioning the knives gives them 




Fig. 43. 



G is a pattern of ogee gutter, 
cutting the ogee. 



M is loop knife for 



solid backing all along the back and up to their cutting 
edge without extra bracing. A single powerful bolt and 
square cap which fits over the knife, as illustrated, are 
usually all that are needed to hold each knife on the head. 
This method of putting knives on a square head gives the 
bolts greater leverage, and as a result the knives are easier 
to hold and the element of danger greatly reduced. 

Knife D, Fig. 40, is designed to straddle the corner of a 
square head and is bolted on both sides, therefore, it requires 
no extra bracing. In making any of the knives shown in 
Fig. 40, good steel of generous thickness should be used in 
order to offset any danger of the knives collapsing while in 
service. The steel for knives A, B and D, should be 3/8-in. 
or 7/16-in. thick while that for knife C should be about 
9/16-in. or 5/8-in, in thickness if the knives are intended 
for making cuts 2-in. or more in depth. Knives of the type 
just described are used quite extensively in Pacific Coast 



BKACES AND KNIVES FOR HEAVY WORK. 73 

mills for cutting different patterns of heavy solid wood 
gutter, one form of which is shown at G, Fig. 43. They are 
also used for various other kinds of heavy cutting. 

Really the best way to make plain deep cuts such as 
gutter, trunking channels, deep grooves, rabbetts, etc., is 
to use sectional slip-on cutterheads. When this equipment 
is available an enlarged section or disc of the required 
width is positioned in line with the deep cut, and the re- 
maining part of the molder spindle simply carries sections 
of normal size cutterheads, either square or round. This 
permits the use of ordinary small knives set at a normal 
projection, therefore braces are unnecessary and virtually 
all danger is eliminated. 

A somewhat crude modification of this idea consists of 
using steel blocks which are bolted to the sides or fitted over 




Fig-. 44. Two kinds of blocks for enlarging square cutterheads. 

the corners of ordinary square slotted heads. Two such 
blocks are shown at A and B, Fig. 44. It will be noticed 
that block A is designed to be bolted to the flat side of a 
square head while block B is made to fit over the corner 
of a square head. Both blocks contain bolt holes running 
thru the projecting parts which fit into the head slots. 
The blocks also contain holes X, X, which are tapped for 
planer bolts to hold the knives. Ordinary knives bolted to 



74 



MACHINE HOLDER PRACTICE. 



these blocks require only a normal projection to make very 
deep cuts. 

Sometimes it is necessary, or at least desirable, to run 
material that finishes an inch or two wider than the rated 
capacity of the molder. For instance, there may be an 
order for 10-in. base and the only machine available is an 
8-in. molder. This means that the surfacing knives must 
extend out over the end of the head l^^ to 2-in. Fig. 45 




Pig. 45. Showing hooks in position for holding ends of project- 
ing surfacer knives. 

shows how the overhanging ends may be supported or braced 
with a pair of iron or soft steel hooks. This is a make- 
shift method but it will serve the purpose very well in 
emergencies provided a comparatively light cut is taken at 
a moderate rate of speed. If the outside head does not pull 
out far enough to clear the work it can be fitted with a spe- 
cial small head or pair of shaper collars and shaper knives 
to make the edge cut. Otherwise the side head can be re- 
moved from the spindle and the outside edge of the wide 
molding finished afterward on a jointer or shaper. 



CHAPTER X. 

- MAKING MOLDINGS IN MULTIPLES. 

In manufacturing large quantities of narrow moldings, 
the cost of production can often be materially reduced by 
working the moldings in multiples or gangs of two, three, 
or more at a time instead of ripping stock into narrow 
strips and running them singly. Of course, there should be 
enough molding of a kind to justify the extra time and ex- 
pense incident to making the more complicated set-up. 
Usually it is not advisable to run anything except stock pat- 
terns in multiples and even they should not be run in gangs 
from good wide lumber if there is plenty of narrow ma- 
terial on hand for making them singly. The extra cost of 
wide lumber must always be taken into consideration when 
planning on converting it into narrow moldings. There is 
certainly no satisfaction in making an imposing display 
of higher molder efficiency by running molding in gangs 
if, after the job is completed and properly figured, it is 
found that the finished moldings are worth less than the 
market price of the wide lumber from which they were 
made. 

Manufacturers of wholesale softwood molding, picture 
frame and embossed ' molding, run most of their narrow 
patterns in multiples of two or more. There is this differ- 
ence in the established methods of making the different 
classes of moldings. In planing mills where large quantities 
of woodwork for building purposes are manufactured, mul- 
tiple work is generally run face down, while in furniture 
and picture frame factories almost everything is made face 
up. Any ordinary pattern of molding can usually be run 
successfully either way altho there are some practical 
advantages in the face-down system under certain condi- 
tions, as mentioned in Chapter VII. The best way to run 



76 



MACHINE HOLDER PRACTICE. 



any multiple molding depends largely upon the profile of 
the molding and the manner in which it is most practical to 
separate the multiples. For instance, if the back of the 
molding is flat, it can be run face down very satisfactory 




Fig. 46. Examples of molding-s made in pairs, face down. 

by surfacing the back with the top head, the square edges 
with the side heads, and finally molding and splitting it, 
as required, with the bottom head, see examples in Fig. 46. 
When this method is followed no wide stock is separated 
into narrow pieces by the top head, hence there are no 
narrow strips to twist, break, buckle nor get out of line 
in the machine. Here is another point, when the knives 
which separate the moldings are on the bottom head, they 



MAKING MOLDINGS IN MULTIPLES. 



77 



do not require such fine depth adjustment as when they are 
positioned on the top head. If the knives which divide 
the moldings cut 1/16-in. or %-in. deeper than necessary, 
it is all right; the points simply cut a little groove in the 
underside of the wood pressure bar and no harm is done. 
On the other hand, this extra length is never permissible 
on the top head unless the bed plate directly under the head 
is recessed especially to accommodate the swing of long 
knife points. 

'' In Fig. 46, five different moldings are illustrated in the 
relative position in which they leave a molder when made 




Fig-. 47. Splitter or center guide in rear end of pressure bar. 

in twos. They are run in pairs of rights and lefts as a 
matter of convenience. Patterns A, B, and C are separ- 
ated by the points of double-edged molding knives which 
cut thru the wood at the dividing line. In order to separ- 
ate patterns like D and E, a narrow straight knife or some 
kind of splitting cutter must be used to cut thru the square 
inside edges. For the purpose of holding the multiples 
apart as they leave the bottom head, after being separated, 
a splitter is fastened in the pressure bar at a point just 
back of where the knives strike, see Fig. 47, This splitter 
serves as a sort of center guide and prevents the moldings 
from shifting or playing sidewise, and thus becoming 
marred at the ends by the bottom head knives. It is not 
always necessary to use a splitter in the pressure bar to 



78 



MACHINE HOLDER PKACTICE. 



separate multiples but in the majority of eases it is very 
advantageous. The question of when and where to use a 
splitter, if at all, is another one of those things which the 
molderman must decide by the exercise of good judgment 
based upon practical experience. 

Where the profile of the molding is such that there is an 
overhanging, unsupported edge left when the bottom head 
knives complete their cutting, wood blocking must be fast- 




Fig. 48. Picture frame moldings made in pairs, face up. 

ened to the rear table, see illustration B, Fig. 46, to pre- 
vent the last ends from caving into the knives as the mold- 
ing leaves the machine. See other examples in Chapter 
VII. 

Referring to Fig. 48, two patterns of picture frame mold- 
ing are shown at F and G as they appear leaving the ma- 
chine when run face up. A great many picture frame 
moldings are run in twos in a manner similar to that illus- 
trated at F, Fig. 48. The top profile and the dividing kerf 
K are cut by knives on the top head while the rabbett E 
is made by knives on the bottom head. The moldings are 
not separated therefore until the rabbett K is cut with the 



MAKING MOLDINGS IN MULTIPLES. 79 

bottom head. Frequently this rabbett is not made on the 
molder at all because it is not desired to separate the mold- 
ings until after they have been passed thru an embossing 
machine and perhaps a molding sander. The rabbett is 
finally cut and the moldings separated by passing the double 
molding thru a machine fitted with solid rubber feed rolls 
and special saws or cutters for milling a wide central groove 
which, when completed, leaves an edge rabbett E on each 
piece of molding. 

SPLITTING CUTTERS. 

Among the many splitting cutters which have been de- 
vised from time to time by moldermen and tool makers all 
over! the country, the few which are standing lip best and 
proving most practical in all respects are illustrated in Figs. 
49 and 50. Eeferring to Fig. 49, cutters A and C are de- 
signed to be fastened with machine screws on the side of 
a block like B, which is bolted in the slot of a square cutter- 
head. Cutter A is part of a saw blade and its teeth should 
be swaged for best results. Cutter C is high-speed steel 
ground thin at the back and near the bottom for clearance, 
and is beveled 45 degi^ees on the front or cutting edge. 
Its mate, which belongs on the opposite side of the 
head is beveled in the opposite direction to equalize or bal- 
ance the cut. Block B, fitting in the slot of a square head 
as it does, serves to hold its cutter perfectly in line. The 
cutter D is made from a section of saw blade and ar- 
ranged to fit into a narrow slot in a steel knife blank E, 
which serves as its holder. The cutter is secured rigidly in 
place by a machine screw as shown. The cutter at F, Fig. 
49, is made from a single piece of steel i/4-in. or 5/16-in. 
thick. The steel is hammered thin, while red hot, and 
^bent and shaped so the front or cutting edge is thicker than 
the back to give clearance. The front concave cutting edge 
is ground hollow with a thin emery wheel so that both 
edges are cutting edges instead of only one as at C, Fig. 49. 



80 



MACHINE HOLDER PRACTICE. 



In Fig. 50, there appears a splitting cutter, a little more 
elaborate in design than those just described. The holder 
is made of soft steel and is in two parts, G and J, which 
are hinged at the back to permit opening the holder and in- 
serting a high-speed steel cutter H. This holder folds up 




Fig. 49. Four types of practical splitting cutters. 

over the cutter in a very compact manner and does not take 
any more room on the head than an ordinary narrow slotted 
knife. The whole device can be attached to any square 
head with a knife bolt. The cutter in this device, like 
those illustrated at A, C, and D, Fig. 49, is removable and 
renewable. 

There is quite a variety of uses which splitting cutters 



MAKING MOLDINGS IN MULTIPLES. 



81 



can be put to in moider work. They serve not only as 
splitting cutters for ripping square-edge stock and separ- 
ating multiple moldings but are also used for creasing or 
kerfing the backs of thick jambs, etc., and for cutting the 
square edges of deep rabbetts and grooves. The chief re- 




Fig-. 50. Special high-speed steel splitting cutter and its holder. 

quirements of a successful splitting cutter are plenty of 
back strength and sufficient clearance. The cutter must 
also be positioned square with the head, perfectly in line 
with the travel of the stock, and needless to say, it must be 
secured in a rigid manner so there will be no chattering or 
vibration when in action. 

Saw tooth splitting cutters like A and D, Fig. 49, should 
be of such shape that the forward or first teeth are pro- 
portionately lower than those at the middle and back, in 
order that the cutting will be evenly distributed among all 
the teeth. Otherwise, a few forward teeth of each splitter 



82 



MACHINE HOLDER PRACTICE. 



will carry most of the strain and do most of the cutting, 
with the result that the cutter will heat rapidly and not 
stand up to heavy work at fast feed. 

While the examples of multiple work appearing in Figs. 
46 and 48 show only simple moldings in pairs, each mem- 
ber of which is the same size and shape, it does not follow 
that all moldings run in multiples are or must be made in 
this manner. There is really no limit to the variety of com- 
binations that can be worked out. Entirely different pat- 




Fig. 51. 



Showing how an extra molding can sometimes be saved 
by under-cutting. 



terns can be paired if desired and, instead of running mold- 
ings in twos, the machine can be set up for making three, 
four, five or more strips simultaneously from one piece of 
stock. So far as the mechanical part of the operation is 
concerned, one might run 12-in. stock in gangs of nar- 
row moldings right along, but considered from a business 
standpoint, this practice is rank folly on account of the 
high cost of wide lumber. 

Sometimes thin moldings are run in gangs but in double 
thicknesses, and they are put thru a band resaw afterward 
to separate them. This practice is occasionally followed in 
the manufacture of screen moldings and other cheap work. 
Other patterns are run double thickness and split apart 
with a circular saw attachment on the rear of the molder. 



SAVING AN EXTRA MOLDING. 



When the profile of any single molding 13/16-in. or 
more in thickness is such that one or both face corners 
must be cut away to a considerable extent, it is sometimes 



MAKING MOLDINGS IN MULTIPLES. 83 

possible to save a small molding or strip by doing a little 
under-cntting as shown at A, B, and C^ Fig. 51. This 
method of making moldings, however, is not practiced very 
extensively and it is not recommended excepting on long 
runs of softwood molding when good lumber, practically 
free from knots, is worked. The method is entirely practi- 
cal and is the means of producing or rather saving an extra 
strip of small molding which would otherwise be cut into 
shavings. If the principal molding of the cluster is made 
face down as shown in the examples in Fig. 51, it is gen- 
erally advisable and often necessary to fasten wood block- 




Fig'. 52. Combination head for splitting- and planing. 

ing onto the rear guides and back table in order to hold 
the moldings solidly in place and prevent them from caving 
in to the knives as they leave the bottom head. 

One more method of gaining an extra strip of molding 
without the use of additional stock is to saw out the rabbett 
of rabbetted patterns, such as jambs, screen door stock, etc., 
instead of cutting it into shavings, with knives. The strips 
are sawed out with either circular saws, splitting cutters, or 
special cutterheads in which square or round-head sections 
carrying knives are combined with circular saws, or parts 
of saws. One type of special head for this purpose appears 



84 



MACHINE HOLDER PRACTICE. 



in Fig. 52. This is used on the side spindle to surface the 
edge and saw under the strip which is saved. The practice 
of saving strips of molding, as described, is followed quite 
extensively in factories making screen doors, bee hives, and 
other stock products which are manufactured in large quan- 
tities. In Fig. 53, there is shown the manner in which a 




BOTTOM HEAD 



Fig. 53. One method of making screen door stock and sav- 
ing the molding. Fig. 54. Machine set-up for making molding 
in Fig. 53. 

strip of screen molding is sawed from the corner of screen 
door stock as the material feeds thru the machine. This 
operation in itself is simple indeed, but when the specifica- 
tions call for a small groove G in the bottom of the fin- 
ished rabbett the proposition is not quite so easy. This 
groove, by the way, is milled for the purpose of receiving the 
wire and a, small strip of wood or rattan which crimps the 
screen wire securely in place. The usual method of milling 
the groove without resorting to an extra operation and an 
extra handling appears in Fig. 54. A small diameter groov- 
ing saw C is suitably mounted directly above the rear 



MAKING MOLDINGS IN MULTIPLES. 85 

table and driven by a separate countershaft, a motor, or by 
a short belt from a narrow pulley alongside the bottom head 
pulley. The strip of screen molding is sprung upward, 
after being cut free from the stock by a saw or cutter on the 
inside head. As the strip advances over the inclined bar B, 
it clears cutter C, and when finished it either falls into a 
trough or is taken away by the helper. The cutter can be 
rotated in either direction because it makes a very light cut. 
The yoke which carries the small grooving saw is removable 
so that it can be detached after a job of this kind is com- 
pleted. 




Gang of splitting- saws mounted on self-centering sleeve for 
use on molder spindle. The saws are separated by spacing 
collars. 



CHAPTER XI. 

MISCELLANEOUS MOLDER WORK. 

There is a vast amount of special work produced on 
molders in various kinds of wood-working factories and 
many freak jobs are occasionally done in jobbing mills in 
emergencies, but since the scope of each of these individual 




Fig. 55. Divided rip saw for use on top or bottom spindle. 

jobs is SO limited it is hardly worth describing all of them in 
detail. For example, there are cases where rope or twist 
molding has been successfully made by turning round mold- 
ing spirally by hand in a form clamped diagonally over the 



MISCELLANEOUS HOLDER WORK. 87 

bottom head of the molder. An occasion seldom arises, 
however, for doing such unusiial work in this crude man- 
ner. Twist molding of practically any design and pattern 
is now made in factories where regular twist machines are 
in operation. A few examples of special work which are 
perhaps of more general interest follow : 

RIPPING WITH DIVIDED SAWS IN GANGS. 

Divided rip saws like Fig. 55, are sometimes used be- 
tween large collars on the bottom spindle of a molder for 
ripping lattice, parquetry strips, and other light work. 
The strips are first planed with the top head and then 
ripped in the same operation. Fine-toothed, hollow-ground 
saws are best for this work because they cut smoothly and 
are easier to fit and keep in order. Plain spring set, or 
swaged saws can be used with good results, however, if they 
are carefully fitted. The halves are held together with 
keys which are fastened on one side, as shown. Being 
divided, the saws can be put on and removed at any time 
without disturbing the boxes. 

RUNNING HEAVY MOLDED CASKET SIDES. 

Wide casket sides, having a narrow piece glued on the 
face side next to the bottom edge to make the base, and. 




N?^<^ STOCK :^^^c;^»:y;^<^ 



MOLDER BED 



Fig-. 56. Position of top rolls for feeding special casket sides. 

sometimes a piece at the top to make a heavy ledge, are 
run face up with the thick edge next to the guide rail. 



88 



MACHINE MOLDEE PRACTICE. 



Altho full-width top feed rolls can be used for this work, 
better results are obtained by the use of narrow rolls which 
ride only on the thin part, as shown in Fig. 56. A sec- 
tional chipbreaker is also used so the thin part of the sides 
can be held down firmly to the machine bed as the sides 
advance to the top head. In running wide material, the 
under-side of the pressure bar should be grooved, recessed, 
or cut away at all points except where pressure is absolutely 
needed. This precaution serves to reduce excessive fric- 
tion betv^een the molding and the pressure bar. Other- 
wise the material will not feed freely, but will stick in the 
machine or tend to "crawl" away from the guide rail. 

MAKING GLUE JOINTS. 

Edge glue joints can be made on a molder on condition 
that the stock is fairly straight and of uniform width. In 
one casket factory the 1x10 common cedar for adult-size 




1 ftg=^ 



B. H 



T.H, 



^7 ^ 



Fig. 57. Line-up of guide rail and inside head for making 
slack-center glue joints. 

casket bottoms is successfully edge jointed on a molder. 
The stock is first roughly cut to about 6-ft. in length and 
then sent to a 15-in. molder where the pieces are surfaced 
two sides, jointed and sized to exact width in one operation. 
A reversable tongue and groove joint is worked on one 
edge with the inside head which is set to take a full ^/i-in. 
cut. The stock is of such size that it does not spring out of 



MISCELLANEOUS HOLDER WORK. 89 

true in the machine provided the latter is in proper align- 
ment and adjusted to feed freely. Accurate setting of the 
jointing (inside) head, guide rail, and outside guides is 
particularly important. In actual practice the operator 
employs a little trick to make the joints slack or slightly 
concave in the center to offset the possibility of some joints 
being full in the center. The trick lies in the adjustment 
of the guide rail back of the jointing head, and it is the 
same scheme that is used to make slack center joints on an 
ordinary glue jointer. A continuous back guide rail is used, 
and at the rear of the machine it is clamped slightly out of 
line as shown exaggerated at A, Fig. 57. This method of 
jointing, planing, and sizing material to width in one oper- 
ation effects considerable saving in manufacturing costs and 
the idea can often be applied to other kinds of work with 
good results. 

RUNNING VERY THIN V^ORK. 

In order to successfully run real thin patterns, one must, 
as a rule, resort to a method similar to that used in plan- 
ing thin veneer, that is, run it on a hardwood board. The 
board is fed thru the machine with the thin material on 
top in practically the same way that a form is used. Ma- 
terial can be planed as thin as 1/32-in. in this way because 
the boards support it as it passes thru the machine. 

MILLING A TAPERED CHANNEL IN WOOD DRAINS. 

A molder on which the bed is stationar}^, and the top head 
and rolls are adjustable vertically, can be used for quite a 
variety of special work. A tapered channel can be milled 
in solid wood, as the stock feeds thru the machine, by gradu- 
ally cranking the head to make a pointer follow a line 
scribed on the outside to correspond to the required taper. 
Square pilaster sides can also be fluted up to a point near 
each end by dropping the top head to cut at the proper 
point and then raising it when the material has fed for- 
ward a distance equal to the required length of the flutes. 



90 



MACHINE HOLDER PRACTICE. 



MOLDING ACROSS THE GRAIN. 

In piano, furniture and novelty plants, certain patterns 
must be molded directly across side and end grain. Piano 
actions serve as a good example of work which must be 
molded smoothly and accurately crosswise instead of 
lengthwise of the grain. Altho ordinary narrow knives 
are sometimes used in this class of work, knives which are 
slightly twisted or ground, and positioned so that they make 



AFTER FIRST RU 




Wp}yx/yAy.yx^yyA 



Fig. 58. Method of making- stair rail in two runs. 

a shearing cut like tenoner and automatic turning ma- 
chine knives, are the most satisfactory because they do not 
pick up nor tear out the grain. Circular milled cutters, 
with an angular face-bevel instead of the usual straight face, 
are also suitable for molding across the grain, especially 
when they are accurately ground so that all wings do an 
equal share of cutting. Usually the material to be run 
crosswise of the grain is planed and sawed into blocks 
which are glued up in lengths suitable for feeding thru a 
molder. In many cases the regular chipbreaker is dis- 
pensed with and hardwood springs are set right up against 
the cutting knives at the point where they begin cutting, 
while the point of a wood pressure bar is set as close as 



MISCELLANEOUS MOLDER WORK. 91 

possible to the point where the molding leaves the cutter- 
head. The object in setting the chipbreaker and pressure 
bar so close is to reduce the open gap for the cutters to a 
minimnm and thereby prevent chipping and tearing of 
grain. It is the same principle that is employed in shaper 
work. 

RUNNING STAIR RAIL. 

A good rule to follow in making stair rail is to place the 
greatest width flatwise and the heaviest cut to the top head. 
This is v^hy so many patterns of stair rail are run on their 
sides instead of straight up. In the latter case, the bot- 
tom of the rail is turned to the guide rail. When large 
quantities of standard stair rail are made, the vv^ork is often 
performed in one operation, but when there is only a small 
amount to make, or if the bottom head is too light to make 
the finish cut, the rail is made in two operations. On 
short runs two operations are often really more economical 
than one. For instance, suppose a rail is the same shape 
on both sides. One set of knives on the top head will serve 
for both runs without any change except to adjust the head 
for thickness. By making the rail in two operations the 
set-up time alone is reduced to less than half. If the pat- 
tern is such that new knives are required a further saving 
is naturally effected by working it in two operations. In 
Fig. 58 is shown a simple stair rail and the method of 
making it in two operations. After the first run the rail 
appears like D, Fig. 58, then it is turned end for end and 
run on a light hardw^ood form as shown at E, Fig. 58. 
During the second run the bottom of the rail is grooved for 
balusters with the inside head. 

MAKING CHURCH SEATING. 

On account of its great width and depth of cut, church 
seating is generally made on a heavy 18-in. molder. While 
ordinary knives and heads can be used for molding church 
seating, a special head with detachable, close-fitting formed 



92 MACHINE MOLDER PRACTICE. 

lips serves the purpose much better because it effectually 
prevents all chipping and torn grain. Heads of this type, 
of course, are only recommended for factories that produce 
large quantities of church seating or other standard work. 
The four corners of the head are milled out to receive four 
formed chipbreakers like M, Fig. 59, which are ground to 




Fig-. 59. Special head, rabbetted to receive formed lips like M. 

match the molding knives. These formed lips or chip- 
breakers are really reversed-knives without slots and are 
screwed down to the head with flat-head machine screws. 
The cutting knives are bolted firmly with planer bolts 
threaded down into the solid head. The cutting edge of the 
knives is set out only about 1/16-in. beyond the correspond- 
ing edge of the formed lips. The result is very smooth 
work, no torn grain, and less strain on the knives. The 
formed lips for church seating are detachable and can be 
replaced with straight steel lips or lips of some other shape, 
if so desired. 



CHAPTER XII 

HIGH-SPEED MOLDEK WOEK. 

The modern high-speed -niolder^ with massive frame, 
hirge journals, wide pulleys, improved feed mechanism and 
m-ultiple bit, self-centering slip-on heads carrying high- 
speed steel cutters, represents the acme of perfection in the 
development of wood-molding machines. Like all other 
fast-feed machines, it is designed to meet the urgent de- 
m_and for increased production and a reduction in the unit 
cost of manufacturing moldings. 

Altho the regulation, square-head molder with feeds 
ranging from 15-ft. to 40-ft. a minute was, and still is, a 
satisfactory machine for making short runs of odd and 
special moldings, millmen recognized long ago the need of 
a faster-feed machine for making standard patterns in large 
quantities. When fast-feed planers and matchers made 
their first appearance some years ago, and startled the 
lumber world by successfully producing high-grade dressed 
lumber, flooring, ceiling, etc., at feeds of 150-ft. to 300-ft. 
a minute, stock moldings were still being run at slow feeds 
and no better or more rapid means of manufacturing mold- 
ing was offered to the trade until a few years later. 

The problem of bringing out a fast-feed molder suitable 
for a variety of vv^ork naturally involved the overcoming of 
more serious obstacles than those encountered in perfecting 
fast-feed planers and matchers. The principles upon which 
the success of the fast-feed idea is based were the same in 
both cases, but the irregular shapes and deep cuts in 
molded work made it necessary to devise different types of 
multiple bit heads and cutters, different knife setting and 
truing devices, etc., than those employed on other kinds of 
fast-feed machines. All difficulties, however, were sur- 
mounted in time and, after passing thru the usual experi- 



94 



MACHINE MOLDER PRACTICE. 




HIGH-SPEED HOLDER WORK. 



95 



mental stage^ the high-speed or rather fast- feed molder 
reached a degree of perfection equal to that of the present- 
day fast-feed matcher. 

AN EXPLANATION^ OF MOLDER SPEEDS. 

The underlying or basic principle which makes fast-feeds 
possible is to get more knives into action at each revolution 
of the cutterhead. Those who have given the subject more 
than casual attention know that when a square-head molder 




One type of six-knife, slip-on round head for top or bottom 
spindle of molder. 

is set up with ordinary knives in the customary manner and 
put into operation, there is only one knife cutting at any 
one part of the stock. There may be a dozen knives posi- 
tioned around the four sides of the head but no two cut 
alike unless by rare coincidence. This statement can be 



96 MACHINE HOLDER PRACTICE. 

verified any time by observing the dust marks on the back 
edge of the knives after feeding a piece of material a few 
inches past the cutting heads. If only one knife of a kind 
strikes the material at each revolution of the head, there 
is only one knife cut per revolution; hence, a molder head 
lotating 3,600 r.p.m makes 3,600 knife cuts a minute. 




Self-centering "vise grip" type of profile head carrying high- 
speed steel, milled-to-pattern cutters. 

Feeding stock at the rate of 25-ft. a minute (300-inches a 
minute) gives a ratio of 3,600 :300 or 12 knife cuts per 
lineal inch v^hich, when other conditions are right, results 
in a comparatively smooth finish. Suppose the feed is in- 
creased to 30-ft. a minute (360-inches a minute) it gives 
a ratio of 3,600 :360 or 10 knife cuts to the inch, which 
means each knife will cut away a little more wood, resulting 
in slightly more chipping and deeper knife marks on 
the surface of the molding. The work may be passable 
but will not be as smooth as that run at the rate of 25-ft. 
a minute. The cutterhead speed might be increased to 4,000 



HIGH-SPEED HOLDER WORK. 



97 



r.p.m. which, with a feed of 30-ft. a minute, would give 
about 11 knife marks to the inch, but it is unwise to run 
molder cutterheads at such high speed because of possible 
vibration, heating of boxes, and the difficulty in obtaining 
a good running balance with the knives and bolts. 

The principle of fast-feed machines is to get more knives 
in action per revolution rather than to increase the revo- 
lutions per minute of the cutterheads. Two knives cutting 
instead of one doubles the number of knife cuts per revolu- 
tion, four knives increases the number fourfqld, and six 



.gj>^ 


k '^'■'.^^^^^^m^^&. 






It 4-^^^^^^^^^^^^ 








1 


*. H 


1 m "'0 s*w^ 




■^^' -^^^m 




^^^^^^~ 


:iiiiiiiapipnii|ii» ^m 




^ 



Two universal chamfer heads set side by side. These cutters 
may be adjusted to cut. practically any bevel desired. 

knives sixfold, etc. AVhen the number of knives of a kind 
on a cutterhead are doubled or increased four or sixfold, 
and all of them are brought into equal action by means of 
knife-truing devices, described later, the rate of feed is 



98 



MACHINE HOLDER PRACTICE. 




HIGH-SPEED HOLDER WORK. 



99 



increased in direct proportion without affecting the quality 
of work. 

There are four factors, each bearing relationship to the 
other, which when taken together, determine the quality 




A three-disc, combination head for grooving- heavy planks, etc. 
Notice enlarged section in middle. 

and quantity of work that can be turned out on a molding 
or planing machine. They are the speed of the cutterhead 
in r.p.m. ; the speed of the feed in feet or inches per min- 
ute ; the number of knives in action on the head ; the num- 



100 .MACHINE HOLDER PRACTICE. 

ber of knife marks (whether visible or not) per inch on 
the finished molding. The relationship which these factors 
bear to each other is expressed by the following rule : The 
product of the r.p.m. of a cutterhead multiplied by the 
number of knives in action, divided by the rate of feed in 
inches per minute equals the number of knife marks per 
lineal inch on the finished work. Perhaps a more clear 
way to express this relationship is by equation form, as 
follows : 

R=r.p.m. of head. 

F=rate of feed in inches per minute. 

K=number of knives on head. 

X^number of knife cuts per lineal inch. 

RK RK FX FX 

X= F= R= K= 

F X K R 

Expressed in proportion this amounts to 

F R 

RK=FX or — =— 

K X 

Note: For the benefit of those not versed in algebra, the times 
sign (x) is omitted between letters which are to be multiplied, RK 
meaning R x K; FX meaning F x X, etc. 

Xow, by substituting known values for any three of the 
letters in the above equations, the third can be calculated by 
the simple formula given herewith, and one can determine 
all the factors upon which depends the quality of work, 
and the speed at which it is run. That is, exact calculations 
can be made as to the speed of cutterheads, speed of feed, 
number of knives in action, and the degree of finish (num- 
ber of knife marks or cuts to the inch). This eliminates 
"cut and try" methods and the usual experimenting with 
ditferent size pulleys and speeds which take up so much 
valuable time, spoil good lumber, and entail extra expense 
for labor and supplies. 



HIGH-SPEED HOLDER WORK. 101 

Wlien making calculations as to the possibilities of vari- 
ous molding and planing machines, as previously described, 
one must keep within certain limitations in regard to the 
figures used to represent the speed of heads, rates of feed, 
and the number of knife cuts per lineal inch of stock. N'o 
hard and fast rules can be laid down in this matter but the 
following recommendations are based upon results of ex- 





Jt 


^^^ 


*. 




J: ^■ 


^^* ^^^ 


^ 


J~ 


i 






l.« 




\\ 





Special combination head for working- one of the many unique 
patterns run at the National Cash Register Company's plant. 

periments and common practice in mills thruout the 
country: 3l^-in. square heads — 3,700 to 4,000 r.p.m. ; 
41/4-in. square heads — 3,300 to 3,600 r.p.m. ; 6-knife 
round heads — 3,000 to 3,200 r.p.m. ; 8-knife round heads 
—2,800 to 2,900 r.p.m. 

Bates of, feed, especially on fast-feed machines, vary ac- 
cording to the quality of finish desired, the kind of machine 
and its equipment, and the facilities available for getting 
material to and from the machine. A great deal of pine 
and fir flooring of good grade is made on fast-feed matchers 



102 



MACHINE HOLDER PRACTICE. 




HIGH-SPEED MOLDEK WORK. 



103 



equipped with automatic feeding tables, at speedsi ranging 
up to 300-ft, a minute, but molding is seldom run at half 
this speed on fast-feed molders. In fact, the average high- 
speed molder is generally rated to feed up to or near 100- 
ft. a minute which is about four times as fast as high-grade 
molding is made on the old-style, square-head machine.. 




Profile beader head fitted with high- speed steel, formed knives. 
Used to work beaded ceiling-, etc. 

Faster feeds are possible, but not always practicable, because 
they do not give the operator sufficient time to properly 
grade and turn the stock as he feeds it. 

. There is also a limit to the number of knife cuts per- 
missible to the lineal inch of feed. Generaly speaking, 
the more knife cuts per inch, the smoother the work, but 
there is a recognized limit beyond which it is unprofitable 
to go. This limit is about 18 cuts to the inch. If there are 
more cuts than this the knives do not "bite" into the ma- 



104 MACHINE HOLDER PRACTICE. 

terial deep enough to cut efficiently and the result is a 
rubbing, scraping action which rapidly dulls and heats the 
knives. Anything between 13 and 18 cuts to the inch pro- 
duces a nice smooth surface; 10 to 11 cuts to the inch 
often gives a passable finish, but less than 10 to the inch 
invaribly shows the knife marks badly, in addition to chip- 



A groove head for flooring. Notice the method of adjusting 
and locking the groover and its holder. 

ping and tearing the grain wherever knots or cross-grain 
are encountered. This, in substance, is the possible and im- 
possible, the practical and impractical in molder speeds and 
quality of finish. It reduces what formerly has been more 
or less an uncertainty and mystery to a simple matter of 
true facts and figures. 

CUTTERHEADS AXD GENERAL EQUIPMENT. 

High-speed molders are built in both inside and outside 
models. The inside type is constructed with four, five, 



PIIGH-SPEED MOLDER WORK. 105 

or six heads and usually fitted with permanent round top 
and bottom heads or cylinders^ each carrying four or six 
knives, as desired. The top and bottom profile arbors at 
the rear end carry interchangeable heads for irregular 
work. Four-side slotted heads may be used on the aibors 
for special work, using ordinary cutters at a slower feed. 
Heads carrying cutters for fast-feed work are of special 
design -and possess the self-centering slip-on feature which 
permits fitting them up completely in the grinding room 
while the machine is in service on other work. The cutters 
are made of high-speed steel ground to shape in the usual 
manner, or milled on the back to the profile of the mold- 



J- 




*.""">, 


w ,.. 




fli 


ILpJL 


Ml 


9 


• 







Fig-. 60. Transverse T-slot head carrying formed knives for 
multiple work. 

ing, as shown in Fig. 60. In either case, the cutting edges 
should be jointed while in motion to bring them all into 
exactly the same cutting circle. Each kind and type of 
cutter has its specific advantages. AVhen there is a large 
quantity and wide range of work it is often profitable to 
have machines and equipment of different kinds and makes, 



106 



MACHINE MOLDER PRACTICE. 



each selected with a view of its adaptability for certain 
lines of work. There are machines which have a much 
wider range than others and consequently can be used for 




Fig. 61. 



One type of knife-setting jig for setting straight thin 
steel knives on round heads. 



a greater variety of work, yet for some particular kinds, 
the machine with the lesser range is more satisfactory and 
efficient. 

In selecting cutterhead equipment, it is advisable that 
every arbor for slip-on heads should be the same size, re- 
gardless of whether the machine is a molder or matcher. 
Top, bottom, side, and profile arbors should be exactly 



HIGH-SPEED MOLDER WORK. 



lor 



imiform size. All sicle-liead sleeves and collars should re- 
ceive all cntterlieads and discs, irrespective of the type. 
This is easily accomplished as mannfacturers will fit ma- 
chines with any size arbor and furnish heads and discs 




Fig. 62. Radial gage for setting knives on square, round, or 
three-wing heads. 

likewise. The importance of this uniform equipment can- 
not be overestimated. It effects a great saving in set-up 
time, cost of cutters, and first cost of equipment. 

To obtain best results and maximum number of pro- 
ductive hours from a fast-feed molder, adequate equip- 
ment must also be provided for balancing, setting, grinding, 
and jointing the cutters. Cutters cannot be set on round 
heads or special high-speed heads with an ordinary molder 
rule. One type of device for accurately gaging the projec- 
tion of straight knives in round heads appears in Fig. 61 ; 
another is shown in Fig. 62. A setting and balancing stand 
fitted with a templet for setting irregular molding cutters 



108 



MACHINE HOLDER PRACTICE. 



quickly and accuratel}^ on any type of cutterhead is shown 
in Fig. 63. 

It is qnite imperative that each one of a set of knives 
placed in a high-speed head be of the same make (therefore 
uniform temper and grade of steel) the same thickness, 
width and lengthy and the same bevel and weight. When 
setting and clamping up a set of knives in a round slotted 
head, the clamp blocks should never be set down hard 




Fig. 63. 



A stand for setting and balancing irregular cutters on 
any kind of cutterhead. 



against any one knife until all of the knives are in the 
head and clamped down fairly tight. When the first knife 
is put in, lock it just tight enough to hold it in place until 
all the cutters are in the head, then each one should be ad- 
justed and the clamp screws set evenly until the head has 
been gone over three or four times, before the clamping 



HIGH-SPEED HOLDER WORK. 



109 



process is finished. If a cutter is clamped to the limit at 
once, while the clamp screws in remaining slots are slack, 
uneven strain is set up which sometimes causes poor work 
and hot bearings. Another method of setting and clamping 
knives in round heads, when making a change, is to 




Pig. 61. Joiiitiny t^lrnight thin .st<-< 1 knives on a rovmd head 
while it is running- at full speed. 

loosen and remove onlv one knife at a time and immediately 
replace the removed knife with a sharp one and tighten 
to the limit before another is ever loosened. The latter 
method is a little quicker than the former but not always 
practicable. 



no MACHINE HOLDER PRACTICE. 



JOINTING CUTTERS ON HIGH-SPEED HEADS. 

After a set of high-speed knives ar,e set as accurately as 
possible to get them with the aid of modern gages and 
knife-setting devices, jointing at full speed is the next 
operation. Since jointing is the final operation before the 




Fig. 65. Jointing thick knives on squaie head. 

head and knives are placed in service, it is a really impor- 
tant one and must be performed with great care and skill. 
There are special stands or aibors on the market for joint- 
ing the knives of slip-on heads, and altho many are in use, 
opinion is divided among practical millmen as to whether 
a cutterhead jointed on an arbor in the grinding room and 
then transfered to the machine will produce as nice a finish 
as a cutterhead jointed right on the machine spindles. 



HIGH-SPEED HOLDER WORK. 



Ill 



When the knives on cutterheads are jointed on a joint- 
ing stand, the jointing arbor, the machine spindles, and the 
self-centering sleeves in the heads must all be mechanically 




Grinding 'straight knives with portable grinder which is 
moved back and forward on a horizontal dove-tail slide or bar 
secured rigidly on the yoke of the machine in accurate align- 
ment with the cylinder. 

perfect and in tip-top condition; otherwise, the jointing 
will never come right. The jointing arbor mnst be the 
same diameter as the machine spindles and mnst rnn 
smoothly and quietly in well lubricated, massive boxes at a 
speed corresponding to that of the molder heads. If either 



112 



MACHINE HOLDER PRACTICE. 



the jointing arbor or any of the machine spindles are the 
least bit out of true or balance, or if either has at any time 
been trued-up after having been in service, the jointing 
will not come right when a head is transfered from one to 




Fig. 66. One type of side-head truing device in position for 
jointing a 4-knife side head for square-edging thin stock. 

another. AVhen all of these little things are taken into 
account, anyone of which will destroy a perfect jointing, it 
is easy to understand why many practical millmen prefer to 
joint cutters while the cutterheads are positioned and 
clamped on the machine spindles. A good jointing arbor, 



HIGH-SPEED HOLDER WORK. 



113 



however, is of inestimatable value in every grinding room 
whether used for jointing cutterheads or not. It serves as 
an excellent machine for testing the running balance of all 
slip-on heads before they are put in service on the ma- 
chine spindles. By trying out the heads for running bal- 
ance in the grinding room, much valuable time is saved 
because any error in balance can be detected and corrected 
before the head is put on the machine. Without this pre- 
liminary running test, errors in balance are often not dis- 




Fig:. 



67. Showing- formed stone and holder for jointing irreg-- 
ular shaped molder knives on top or bottom head. 



covered, if at all, until after a head is placed in service and 
then it is generally a temptation to let it go. A poorly 
balanced head on a molder spindle results in poor work, hot 
boxes, and eventually worn bearings. 

Best results in jointing are obtained by doing the work 



114 



MACHINE HOLDER PRACTICE. 



while the machine is warmed up and the journals are 
flooded with oil. Joint lightly always. Let the "touch" of 
the stone, the faint whir of the knives and the appearance 
of a small, dark-red spot on the end of the stone tell when 




Fig-. 68. Another type of side-head jointer and a special 
four-wing-, fast-feed head fitted with self- centering- sleeve and 
thick high-speed steel cutters. 

the stone is in action rather than crowd the jointing until 
a stream of red sparks fly into the air. Heavy jointing is 
ruinous because it produces such a heavy heel that the 
knives pound and raise the grain instead of cutting freely 
as they should. Also, the edge of the cutters will burn if 
the feed stops for a moment. On the other hand, when the 
knives are jointed lightly, they will stand several jointings 



HIGH-SPEED HOLDER WORK. 



115 



(each of which renews the cutting edge) before they re- 
quire regrinding. 

The device generally used for jointing straight knives 
on top and bottom heads at the machine consists of a per- 




Fig. 69. Side-head jointing attachment in position for joint- 
ing the formed cutters of a matcher head. 

fectly straight slide bar with a movable carriage accurately 
fitted thereto which carries a jointing stone. The slide bar 



116 



MACHINE HOLDER PRACTICE. 



is set absolutely parallel to the cutting cylinder and secured 
rigidly in place so the jar or vibration of the machine 




Fig. 70. Shewing: one type of jointing device attached to 
slide bar on a jointing and setting stand. Self-centering heads 
are set up, tried for running balance and jointed at full speed 
on the stand, and then transferred to molder spindles. 



cannot effect it. During the process of jointing the car- 
riage is moved slowly from end to end while the cutter- 
head is revolving at full speed. Provision is made for 
moving the jointing stone toward or away from the cutter- 



HIGH-SPEED HOLDER WORK. 117 

head and for holding it firmly to the work^ see Pigs. 64 and 
65. 

The devices for jointing straight knives on side heads 
are similar to those used for top and bottom heads. They 
are designed to be fitted to the machine frame at a point 
near each side head. The jointer-stone carrier works snug- 
ly on a vertical slide which sets parallel to the side head. 
Both vertical and horizontal adjustments are provided so 
the stone can be moved to-and-from end to end of the slide 
with ease and accuracy, see Figs. 66, 68 and 69. 

There are two methods commonly used for jointing ir- 
regular shaped knives. One is to prepare a formed stone, 
one edge of which must be made exactly the same shape 
as the profile of the molding. This formed stone is 




A two- disc combination on self- centering clamp sleeve. Steel 
jointing- form, in two sections, appears at right. 

clamped in the stone carrier and positioned so it lines up 
exactly with the molding cutters on the head, see Figs. 6v 
and 68. The carrier is then clamped fast to the side bar, 
the stone backed away from the knives, and when the head 
is running full speed the stone is advanced slowly and 
carefully until it comes in contact with the edges of the 
whirling knives. If the knives have been ground and set 
with extreme care and accuracy a slight touch with the 



118 



MACHINE HOLDER PRACTICE. 




One type of pedestal head grinder for grinding- knives on self- 
centering side and profile heads. 



HIGH-SPEED MOLDER WORK. 119 

jointing stone will be sufficient to bring them all into a 
uniform cutting circle and make each do an equal share 
of cutting. The other method consists of using a device like 
that attached to the jointing stand shown in Fig. 70. A 
steel templet or pattern is clamped to the bar and a pointer 
which is arranged to travel on this formed pattern guides 
a narrow jointing stone in such manner that the exact pro- 
file of the pattern is reproduced on the cutters. The steel 
patterns or templets can be purchased from manufacturers 
or made in the grinding room to suit the form of cut de- 
sired. 

After the heads have been fitted and positioned on their 
arbors, the operating of a fast-feed molder does not difl:er 
greatly from that of a slow-feed machine. The adjusting 
of the rolls, bed, guides, and pressure bars is done in prac- 
tically the same manner as on the old-type machine. How- 
ever, in the case of cutterhead bearings there is a difference 
because, when using high-speed heads and jointed cutters, it 
is necessary to always have the bearings absolutely tight and 
well lubricated in order to keep all knives cutting in such 
a manner that they will produce a perfect surface on the 
finished molding. The adjustment of the cutterhead heal- 
ings, however, does not have to be made as often on a f a?t- 
feed machine as on the old-style, slow-feed machine be- 
cause the journals are larger, caps are moie securely 
clamped, and the massive boxes are mounted in heavy, 
powerful yokes which positively hold them in place when 
once adjusted. 

In making short runs of special molding the method used 
is virtually the same as on the square-head machine. 
Square heads are slipped onto the spindles and clamped by 
a self-centering device. The regular knives used in detail 
molder work are used in the same way as on the old-type 
machines and about the same rate of feed is carried. 

The fast-feed molder is not confined to molding work 
alone. Owing to its rigid design and powerful feed works, 



120 



MACHIXE MOLDER PRACTICE. 




HIGH-SPEED HOLDER WORK. 



121 



it will do the ordinary work of both a fast-feed matcher 
and double surfacer and is frequently used as such. It is 
also particularly adapted for heavy work when fitted with 
square slip-on heads on account of its heavy, powerful con- 
struction. Since its greatest advantage, however, lies in 
making long runs of stock molding, a good supply of slip- 
on heads and high-speed steel cutters should be kept on 
hand at all times to make the various patterns of molding 
regularly manufactured. 




Inserted, swaged-tooth ripping saw, with clamp collar and 
self-centering- sleeve, for use on a niolder spindle. 



CHAPTEE XIII. 

KNIFE MAKING. 

The designing and making of knives is an art that 
should be thoroly understood and mastered by every 
mechanic who aspires to become a first-class molderman. 
Heretofore, the opportunities for an apprentice or the 
uninitiated to learn knife making have been few indeed. 
More or less secrecy has always been thrown around the 
principles and correct practice of designing, shaping, and 
tempering molder knives, with the result that many molder 
operators are not acquainted with the most up-to-date 
metliods in this interesting and important part of their 
trade. 

Previous to the advent of modern high-speed steels, 
which require no heat treatment, carbon steel was used ex- 
clusively for all straight and irregular molder knives. Be- 
cause of the comparative low cost, and its satisfactory per- 
formance on detail and short-order work, carbon steel is 
still widely used in woodworking factories. It is usually 
purchased in slotted blanks already cut to length and 
width, and beveled at the cutting edge. It also comes in 
the form of rectangular bar steel of various sizes. As a 
rule, steel for slotted knives is bought in slotted blanks 
about %-in. thick, while stock for spike knives comes in 
straight bar steel %-in. to 5/16-in. thick and %-in. to 
li/2-in. wide. 

When ordering knife steel for one or more molders in a 
plant, always specify the same thickness, especialy in the 
case of bar steel for spike knives. It is best to stick to 
one brand of steel as long as that particular kind is giving 
good results. Cheap steel is expensive at any price and 
should never be considered under any circumstances. 

The first thing in knife making is to determine the 



KNIFE MAKING. 12.') 

design and size of cutter or combination of cutters most 
suitable for the work at hand. To design a knife intelli- 
gently, one should know how the molding is to be run and 
the kind of wood that is to be worked. The design of a 
single knife or group of knives for any particular pattern 
depends more or less on the number of cutterheads to be 
employed and whether the molding is to be run face-up 
or face-down, flat, on edge, or at an angle, etc. If the 
material to be worked is curly-grained hardwood, or if it 
must be molded across side or end grain, the knives will, of 
course, have to be designed to meet such conditions. A 
number of common and special knives for various kinds of 
work have already been illustrated and described in pre- 
ceding chapters. The reader is further reminded of v^hat 
was said in Chapter III about the advantages derived by 
using sectional knives instead of a single solid knife, es- 
pecially when making complicated patterns. When plan- 
ning a new knife, avoid all inside corners and other shapes 
that require the use of a file for sharpening the cutting 
edge. A knife that must be filed requires a filing temper, 
therefore it cannot be depended on to hold a sharp cutting 
edge. It dulls rapidly and often loses its true shape after 
being sharpened a few times. Knives that can be com- 
pletely ground to shape on a wheel are more satisfactory 
in every way. They are easier to sharpen and can be 
given a harder temper along the cutting edge. 

Knives to cut wide sweeping curves such as shallow 
ogees, ovals, etc., are generally made in one piece rather 
than in sections. because, in cases of this kind, one knife is 
easier to make and set than two. Under such circum- 
stances, a single solid knife is all right provided the cut 
is not too deep and the material is comparatively straight 
grained. Otherv^ise the cut should be divided between two 
or more knives positioned on different sides of the head. 

Moldings which are rabbetted to overlap base, wainscot- 
ing, or any woodwork %-in. or more thick, are almost in- 



124 



MACHINE HOLDER PRACTICE. 



variably made as shown in Fig. 71 in preference to the man- 
ner illustrated in Fig. 72, because the former method saves 
considerable lumber. When molding is turned at any angle, 
and run in this manner, the knives must be designed accord- 
ingly. Sometimes by turning a molding, as shown in Fig. 
71, a light under-cut is necessary, whereas, if it is made 
like Fig. 72, no under-cutting is required. This is another 
case where one must use sound judgment in deciding upon 
the best practice rather than follow any hard and fast rules. 
Usually if there is a large quantity of molding to make, the 



FIG. 71 




Fig-s. 71 and 72. Notice the saving in stock effected when mold- 
ing- is run as shown in Fig. 71. 

saving in lumber is of far greater importance than the- 
little extra trouble required to tilt the side head to make a 
small under-cut. 

Never attempt to make a deep cut with a long, slender 
knife. Thick steel knives should be used for making deep 
cuts, and wherever possible, each knife should be of extra 
width to give added strength. Before making a new knife 
be sure the steel blank is neither too long nor too short for 
the head. If too long it can be cut down, of course, but if 
too short it cannot be used. With the design and size de- 
termined, the next thing in order is to grind the steel to 
correct shape and bevel to produce a knife which will cut 
the desired profile. Knife shapes for bevels and straight 
cuts are simple enough, but a knife which will cut a true 
quarter or half-round, a cove, ogee, reverse ogee, or any ir- 
regular curve, is not so easily ground to shape until one 
has had some practice at the work. 



KNIFE MAKING. 



125 



Owing to the angle at which knives on square heads are 
presented to the work, they must project farther from the 
lip of the head than the straight-down measurement of the 
corresponding cuts which they make, see Figs. 73 and 74. 




Pigs. 73 and 74. Notice how the cutting angle changes with 
depth of cut. Fig. 75. Method of laying out molder scale. 

The angle at which molding knives do their cutting is by 
no means constant, but varies slightly according to size of 
the head, and considerably according to the knife projection 
or depth of cut. Thus, in Fig. 73, a surfacing knife on a 
4-in. head (reduced to scale) swings past the point of its 



126 



MACHINE HOLDER PRACTICE. 



deepest cutting at an angle of about 50 degrees, while in 
Fig. 74, a knife cutting yg-iii- deeper on the same size head 
finishes at an angle of 61 degrees. 

The exact amount of knife projection required for cut- 
ting different depths is obtained by making a full-sized 



T SQUARE 




Fie: 76. Method of laying out knife profile with small drafting 
outfit. 

layout of the cutterhead with at least one knife in position, 
see I'ig. 75. Make an allowance of about 3/32-in., or 
enough to properly clear the knife bolts, for the projection 
of surfacing knives, as at B, Fig. 75. From the center of 
the head draw line C B A, and on" line B A start at B and 
lay off Vs-in. divisions from a rule. Continue the knife 
line K B to D. Then with the compass point at C, extend 



KNIFE MAKING. 127 

the Vs-i^- divisions from line B A to the knife projection 
line B D. The divisions on B D represent the true molder 
scale for this size head. Close examination of this layout 
discloses the fact that while all of the divisions on line 
B D are slightly more than Vs-iii- i^ length;, they gradually 
decrease in length as they recede farther and farther from 
the head. This point is mentioned to explain clearly why 
no molder scale can be reversed. 

NoW;, when the molder scale is laid out, as just described,, 
it can be transferred to a hardwood, metal, or celluloid 
gage as shown in Fig. 75, or it may be scribed on either 
a little brass T-square or the edge of an ordinary rule. It 
can then be used for laying out new knife shapes to guide 
one in both the grinding and setting operations, see Chapter 
IV., "Setting Up a Molder". 

Fig. 76 shows a method of laying out knife shapes with a 
small drafting outfit. A full-size head is laid out per- 
manently on a small drawing board. The sides of the head 
are square with the edges of the board, and knife line K B 
D is parallel to the line of actual measure C Y A. The 
horizontal base line X Y Z intersects vertical line C Y B 
at right angles and is tangent to the cutting circle of the 
surfacing knives. A tracing of the full-sized molding is 
tacked to the board so that its inside edge lies on line Y A 
and its highest point touches line X Y, as shown in Fig. 
76. Now, with the T-square, draw horizontal lines thru 
important parts of the molding and let them intersect 
vertical line Y A. With the compass centered at C, extend 
these lines to the knife projection line B D. At points 
on the molding-outline where the horizontal lines inter- 
sect, square up as at 1, 2, 3, 4, 5, etc. Then square back 
across with T-square from the intersections on line B D 
and, where the vertical and horizontal lines intersect di- 
rectly above the molding, the correct knife profile can be 
traced, as shown in Fig. 76. This method of laying out 



128 MACHINE MOLDER PRACTICE. 

knives is accurate but slow, and therefore only recom- 
mended for study practice and use in drafting rooms. 

Expert knife makers use neither the drafting system 
nor the sticker rule for obtaining correct shapes, but im- 
mediately begin grinding the knife to shape on a coarse, 
free-cutting wheel without any preliminaries whatever. 
First the knife is ground to a shape exactly the reverse of 
the molding, then ground deeper to make allowance for the 
greater knife projection. At this stage of the process one 
is guided by good judgment and a practiced eye. As the 
grinding nears completion the knife is taken from the 
wheel repeatedly and held over the drawing, or fitted to the 
sample at the angle which it cuts. The angle is changed for 
deep and shallow cuts as dictated by keen judgment. By 
sighting down over the edge of the knife to the outlines of 
the drawing or sample, one can tell when the shape is right, 
and when right, the clearance, bevel is ground. This 
method of grinding knives to shape is not guesswork, as 
one might presume, but is a matter of skill and practice, 
being used by some of the most accurate and fastest molder- 
men in the country. By using this system, a rapid work- 
man will have a knife half completed in the time that it 
ordinarily takes to lay out a knife shape with pencil and 
paper. 

Before leaving the subject of knife shapes, it might be 
well to explain a little point over which there has been some 
argument and speculation among moldermen. The question 
is, why a straight miter or bevel cannot be cut with a 
straight-edged knife. The fact of the matter is that a 
straight-edged miter knife cuts a slightly convex or curved 
miter, while to produce a really straight miter or bevel the 
knife must be slightly curved (convex) instead of straight. 
This apparent paradox is due to two things : the elongation 
of the cutter to conform to the elongated molder scale, and 
the fact that the cutting angle of the knife changes ac- 



KNIFE MAKING. 129 

cording to the depth of cut. The layout of a miter knife 
in Fig. 77 shows the slight curvature clearly. 

Another thing worth remembering about knife shapes 
is that a knife ground to cut a perfect quarter-round or 
half-round is part of a true elipse. One method of laying 
out knives to cut perfect quarter and half-rounds appears 
in Fig. 78. A wood-turning of the proper diameter, how- 
ever, is probably the best thing to use in trying out a 
quarter or half-round knife to prove its accuracy before 
putting it in service. Moldermen who have occasion to 
make a great deal of round molding will find it advan- 
tageous to prepare a stick with different diameter sections 
turned along its length for this purpose. 

Knives for round heads can be drafted .and ground to 
shape in a manner similar to that just described for square 
heads. The principle is exactly the same in both cases. 
The proper bevel for the edge of molding knives depends 
largely upon the size of the head and the angle at which 
the knives cut. There must always be more than enough 
bevel for back clearance in order to give an acute cutting 
edge and prevent any possibility of shavings catching be- 
tween the heel of the knife and the finished molding. 
Knives for comparatively shallow cuts should be beveled 
on the edge about 33 to 36 degrees, while those for deeper 
cuts may be given an edge-bevel of 40 to 45 degrees, see 
Figs. 73 and 74. The reason for the shorter bevel on long 
knives is to give greater strength at the cutting edge. The 
amount of bevel for side clearance need never be more than 
5/16-in. or %-in. to the inch, or about %-in. to the thick- 
ness of an ordinary knife. 

Knives made of carbon steel must be given heat treat- 
ment, followed by quenching in oil, water, or some liquid 
solution to give them the proper degree of hardness or 
temper along the cutting edge. A knife that has slender 
points should not be ground to finish size until after re- 
ceiving heat treatment. A new knife edge should be left 



130 



MACHINE MOliDEH PRACTICE. 



thicker at all narrow points and corners so that when it is 
being heated at the forge these points will not be so likely 
to heat too rapidly and burn before the rest of the knife 
becomes red hot. If the knife is to be heated in an open 
forge, use old coals or charcoal for the fire in preference to 
fresh coal because the latter may contain sulphur or other 



/ r 
1 

\ 
\ 

\ 
\ 


-1 
CENTER 


OF HEAD 


1 
/ 
/ 
/ 

^B 

^E 
^F 
'G 
■H 
-1 

ROFILE 


\ 

1 


L 

B 

c 

D 

E 


\ 

_L — , -, 

\ /^ 


1 \P^"""- 


\ MITERED STOCK ^\:-- 
1 ^ 


G 

H 


— "^"Tl- "KNIFE P 










1 



Fig. 77. 



Layout of a knife to cut a miter, 
curvature of knife edge. 



Notice the slight 



chemical properties that may injure the steel. Before put- 
ting a knife into a forge fire, it is important to have a 
heaping bed of red hot coals. Lay the knife face up on the 
hot coals and concentrate the greatest heat a little back of 
the beveled heel. Never heat the cutting edge first. See 
that the heat plays uniformly along a line about y^r^TL. or so 
back of the heel. This uniform heating, which is so im- 
portant, is accomplished by turning and shifting the knife 



KNIFE MAKING. 131 

with the tongs. Operate the bellows slowly to give a quiet 
but positive draft until an even dark red appears along the 
entire edge of the knife and %-in. or more back to the edge. 
Heating along back of the heel^ as directed, permits the heat 
to spread more evenly and prevents the sharp cutting edge 
from overheating. If perchance a slender point on the edge 
heats too rapidly, withdraw the knife and cool that point 
either on cold iron, in tallov^^, or oil, then replace the knife 
and continue heating it. Never let a knife lay on or in hot 
coals to absorb heat, but try to keep its temperature rising 
and quench it at a rising heat. 

As the knife gradually becomes a little brighter than dull 
red, push the entire edge into the coals, and then when it 
is a cherry red (a shade between dull and bright red) 
withdraw the knife quickly and plunge it point downward 
into a bucket of linseed oil, fish oil, or some suitable quench- 
ing liquid, and stir it vigorously to cool quickly and tho- 
roly. When the knife is cool, wipe it dry and try the 
beveled cutting edge with a file. If it files easily, it is too 
soft. Should the file glaze over it like glass and not bite, 
the edge is then too hard and must be tempered to reduce the 
degree of hardness. When the file takes hold on the edge 
and bites with difficulty, the edge is just right. A knife 
that is found to be too soft after heating and quenching, as 
described above, has evidently not been heated hot enough 
or else not quenched quickly and thoroly while at a 
rising heat. A knife that is a little too hard can be easily 
tempered. First brighten the edge and face with sand- 
paper or some abrasive; heat it some distance back from 
the edge on a red hot iron or over the hot coals in the 
forge. After a little heating, colors will begin to appear. 
When a yellov^ or straw color spreads to the cutting edge, 
remove the knife and cool it. This usually gives a good 
temper for wood cutting and the edge can barely be 
scratched with a file. 

There are several different ways of quenching steel after 



132 



MACHINE HOLDER PRACTICE. 



it has been heated to a cherry red. Often the method is 
varied somewhat to suit the kind of steel or quenching 
liquid available. Some knife makers prefer about i/2-in. of 
oil on top of the water. They dip the knife into the oil 
slowly, heel first, passing it slowly thru the oil and into 
the water until the knife becomes black. Then it is quickly 
withdrawn and polished on the edge and face. TJsually 
enough heat remains in the part held by the tongs to temper 
the edge. The colors begin to appear as the knife is held in 
the air, and when a yellow spreads to the edge, the knife 
is cooled in v^ater. This is a rapid method because only 
one heat is used for both the hardening and tempering. 

In the absence of oil, water is sometimes used for quench- 
ing but is not recommended because it may crack the steel 
or make it so hard and brittle that it will crack when in 
service. If water must be used, the knife should be slowly 
dipped into it, heel first, but only at the surface however. 





















MOLDER SCALE 




llJ 
_1 
< 

z 


1 


^^^^^"^^ 






) 





















Fig. 78. One way to lay out quarter and half-round knives. 

then withdrawn and dipped again, each time a little deeper, 
repeating the process until the knife is black. Then polish 
quickly and temper as described. 

There are a number of so-called secret solutions for 
quenching steel, and while some give good results, they arc 
all more or less expensive and very few excel good linseed 



KNIFE MAKING. 133 

oil or a combination of fish oil, linseed oil, and tallow. 
Plain lubricating Al can be used with fairly satisfactory 
results. Oil of one kind or another is prefered to water on 
account of its milder action as a cooling agent. 

After a knife has been properly tempered the edge 
should be ground smooth and sharp, and whetted lightly 
with a whetstone. It is then ready for use. To preserve 
the exact shape of irregular stock knives, patterns to fit the 
cutting edge can be made of sheet metal and filed away 
with either the knife, the molding sample, or set-up temp- 
lets. 

Bar steel for spike knives is generally cut into lengths 
suitable for knives by grinding deep grooves across the 
side with a thin emery wheel and then breaking off the 
pieces in the vise. When following this method, grind the 
grooves on one side only, as shown at A, Fig. 79, not on 
both sides as at B, Big. 79. The latter is a very wasteful 
practice and requires considerable more grinding to attain 
the cutting bevel. 

The practice of heating and swaging or spreading the 
cutting end of spikes by hammering, see Fig. 80, before 
they are giound or tempered is very good because it gives 
a wider cutting edge and leaves less to do w^hen beveling 
the edge. It is also claimed that hammering hot steel 
during the swaging process tends to compress it and make 
the cutting edge more tough. 

Knives for cutting wood across the grain are often 
twisted or forged to a curve to give the cutting edge a 
shear cut similar to the angle of knives on automatic lathes 
and tenoner heads, see Fig. 81. A shear cutting knife with 
a hard edge produces much smoother work than straight 
knives. Twisted knives are sometimes used for making 
deep, perpendicidar or nearly perpendicular edge cuts v^ith 
the top or bottom heads. The twist gives the knife an 
acute cutting angle at the side, therefore it cuts easier and 
stays sharp longer than if it was flat and made a side scrap- 



134 



MACHINE HOLDER PRACTICE. 



ing cut. Knives should always be designed to cut freely, 
especially at the sides, because if they scrape or rub the 
wood, the friction causes them to heat and dull rapidly. A 
knife will never burn black if it is cutting freely, but it will 
do so in a few minutes if allowed to rub on the edge of 
stock or between two strips of multiple work. 

Holder knives should always be arranged orderly in 




FIG. 80 ^ 



FIG. 81 



Fig. 79. Correct and incorrect way to cut off bar steel with 
emery wheel. Fig-. 80. A spike knife, spread "or swaged at end. 
Fig. 81. A twisted knife. 

clean racks so that no time need be lost in finding particular 
kinds. In large up-to-date factories, knife racks, grinding 
w^heels, forge, vise, balancing scales, set-up equipment, etc., 
are kept in a separate, well-lighted room called the grind- 
ing room. The knife making, gi'inding, balancing, and 
selecting of cutters for several molders is all done by 
an expert molderman. The machine operators simply do 
the setting up and tend to their machines. In small plants, 
however, the knife rack is often purposely placed near the 



KNIFE MAKING. 



135 



molder so that while the operator is feeding the stock on 
one job of molding, he can also be picking out and balanc- 
ing cutters for the next Job. In some California factories, 
a knife rack is built right over the countershaft of each 
molder, and in front of the rack there is a narrow work 
table or shelf with drawers for bolts, waste, and other 
paraphanalia. The balance scales sit on the shelf ready for 
instant use. While feeding the molder on one order, the 
operator selects his cutters and balances them for the next 
job. This is one of the little conveniences that enable the 
"speed kings" to make so many set-ups a day. 




A three-disc side head tipped to show self- centering sleeve. 



CHAPTEE XIV. 

BABBITTING HIGH-SPEED BEARINGS. 

Babbitting the boxes, which carry high-speed spindles, is 
very particular work and calls for the exercise of both 
skill and good judgment. On some machines there is a 
brass name-plate bearing the words, "Never babbitt on a 
cutterhead journal ; you may spring it, and once sprung it 
cannot be permanently repaired ; use a babbitting mandrel.'^ 
This is good advice and should always be followed when 
possible. The greatest danger in springing a journal is 
when the hot metal is poured directly onto it, and only on 
one side, to cast a half box. The sudden expansion during 
the time of pouring, and slow contraction later, is likely 
to produce a permanent set or slight bend in the journal 
which will cause trouble by heating and running badly. 

When a journal, however, is wrapped with two thick- 
nesses of thin paper and both top and bottom boxes are 
poured at the same time, there is scarcely any danger of 
springing it. Still there is an element of risk in the latter, 
hence the safest course is to always use a babbitting mandrel 
made of an old spindle, shaft, or stick of hardwood turned 
to the same diameter as the journal. 

A mandrel should be wrapped with two thicknesses of 
thin paper and the ends pasted down with mucilage or 
photo paste. The paper enlarges the mandrel just enougli 
to take care of the shrinkage of babbitt in cooling. Babbitt 
also casts more smoothly around paper than it does around 
a naked metal shaft. The mandrel must be carefully and 
•firmly secured in exactly the same position that the cutter- 
head spindle assumes while running. In other words, if 
one or both boxes for a top, bottom, or profile spindle are 
to be babbitted, the mandrel is placed level and square with 
the machine bed. If only one box is being cast, it must 



BABBITTING HIGH-SPEED BEARINGS. 



137 



line up with its mate. When both are to be cast, the man- 
drel should always be placed as nearly in the center of the 
boxes as possible. In adjusting a mandrel for side-head 
boxes, set it plumb with the machine bed. 

It is generally much more convenient, when preparing 
to babbitt side-head boxes, to detach the yoke in which the 
boxes are mounted and take it to the repair room where 
the work can be done in good light near the forge. Align 
the mandrel parallel with the planed ways of the yokes. 




Fig. 82. Showing lower half of the box prepared for bab- 
bitting-. S, babbitting- mandrel wrapped with paper. L, L, 
liners. W, W, washers at ends. R, R, putty. 

Clean out all old babbitt, especially that in the anchor 
holes and plug up any oil holes or chambers which may be 
in the bottom box. Oil holes can be easily plugged with 
bits of wood whittled round to fit them. Oil chambers, 
however, should be packed with waste and the opening 
covered with a piece of belting thick enough to fit in snug- 
ly between the box and the babbitting mandrel. This piece 
of belting backed with waste, not only keeps the hot metal 
from running into the oil chambers or between the mouth 
of the chamber and the mandrel, but also serves as a shim 
which assists in centering and supporting the mandrel in 
the box. 

A very simple and easy method of centering and sup- 
porting a babbitting mandrel is to place a narrow strip 



138 MACHINE HOLDER PRACTICE. 

of belting crosswise of the box, letting it extend less than 
half way around the mandrel to leave plenty of room for 
melted babbitt to flow in all parts of the box. After the 
box has been cast, these strips of leather may either be 
left in position or replaced with felt. When both top and 
bottom boxes require new babbitt lining, considerable time 
can be saved by arranging to pour both boxes at the same 
time. As in all cases, the edges of the boxes must be 
separated by liners to provide enough take-up adjustment 
for wear. A plan or top view of the bottom half of a 
bearing ready to be poured in the manner recommended 
appears in Fig. 82. The liners L, L are made of cardboard 
or thin wood and have small V-notches, as shown, to per- 
mit the melted babbitt to flow from the top half of the 
box down to the lower half. When the metal cools, it will 
be joined together at the V-notches, but these slender con- 
nections are easily broken apart by a few taps of the ham- 
mer on the end of the top box, or the prying action of a 
chisel. If only the top half of the box is to be cast, the 
liners are not notched at all. 

After the oil holes and chambers are plugged and the 
babbitting mandrel is properly centered and clamped in 
place between liners, see Fig. 82, the cap (top half of box) 
is set over the mandrel and clamped or bolted down against 
the liners. Leather or cardboard washers W, W, Fig. 82, 
are then placed at each end and the end openings sealed 
with putty, clay, dough, or a mixture of asbestos and oil, see 
R, R, Fig. 82. Two open holes should be left in the top of 
the cap, one for pouring the metal and the other for a vent 
to permit the escape of entrapped air. Care must be taken 
that no moisture is present in the boxes when the metal is 
poured or a "blow-out'' will result from sudden forma- 
tion of steam. If the work is done in a cold atmosphere, 
the boxes and mandrels should be warmed before the metal 
is poured. This avoids chilling the hot metal and permits 
the box to shrink somewhat with the metal when both 



BABBITTING HIGH-SPEED BEARINGS. 



139 



cool, thereby preserving a firmer connection between the 
two. 

When everything is in readiness, the babbitt is melted in 
a regular ladle. In the absence of a proper instrument for 
taking the temperature, one must simply use good sense 
in heating the metal, not too hot, but hot enough that it 
will run freely into all parts of the box before it begins 



i — H — H r~ 



Fig. 



83. Oil channels spread in direction of rotation from 
supply holes, H, H. 



cooling. The temperature at which babbitt should be 
poured is about 450 to 460 degrees C. Pour the metal in 
a steady stream, being careful' not to let any of the top 
6lag enter the box and be sure to have enough metal to fill 
the entire box with one pouring. Do not disturb the newly 
cast box until it has cooled ; then take the boxes apart and 
smooth off all rough or sharp edges with a chisel or rasp, 
and babbitt scraper. Open the oil holes, and chambers if 
any, and cut oil channels from them to points near the 
ends of the box, as shown in Fig. 83. The function of 
the oil channels is to facilitate the flow of oil to all parts of 
the bearing, therefore, they should lead outward from the 
supply holes in the direction of rotation. Their edges and 
those of the boxes should be rounded because sharp edges 
tend to scrape oil off the journal and prevent its proper dis- 
tribution. 

Every babbitted bearing must be carefully scraped to fit 



140 MACHINE HOLDER PRACTICE. 

its journal perfectly. Otherwise, the jt)urnal will bear only 
on high spots and all lubricant will be forced into the low 
places where it will not do any good. Under such condi- 
tions, overheating is certain to occur, even tho the bear- 
ing is flooded with oil. In order to know where to scraps, 
give the journal a very thin coating of red lead paint and 
turn it around in the boxes. The bright spots show where 
the surface must be scraped. A\^ien the fit between journal 
and boxes appears to be perfect, bolt the latter in place, put 
on the belts, and run the spindle up to speed for a few 
minutes. Take the boxes apart again, and the bright 
places caused by friction show exactly where to do the light, 
final scraping. This all takes time, but is worth it, because 
it produces smooth-running, non-troublesome bearings 
which are so essential to good molder work. 

When adjusting new boxes to a high-speed journal, do 
not make the mistake of clamping them down too tight. 
Leave a little play at first and run the spindle at full 
speed for a while to let it warm up. The expansion from 



B 



Babbitt scrapers are visually made by g-rinding a half-round 
file as shown at C, or a three-cornered file as Illustrated by 
cross-section D. 

heating may be enough to take up all lost motion, but if it 
is not, then tighten the boxes just a trifle while they ar(3 
warm. 

In babbitting a box which receives a grooved journal 
(grooved to prevent side play in the spindle) the usual 
practice is to give the journal a good coat of white lead 
paint, and then use it as a mandrel for molding the babbitt 
lining. A wood mandrel with corresponding grooves can 
be turned by an expert turner if a templet is provided, to 



BABBITTlNGt PtlGH-SPEED BEAlliNaS. 141 

fit accurately into the grooves. The wood mandrel is rec- 
ommended because, if a grooved journal is sprung the least 
bit, it is practically ruined forever. 

The lubrication of high-speed bearings is of great im- 
portance. To run properly, a journal and its bearings must 
always be separated by a thin film of oil. It is quite im- 
perative that good oil be used and the supply be kept con- 
stant in order to maintain perfect lubrication. It is often 
necessary, especially on large bearings, to introduce oil from 
the bottom as well as the top. If there is no provision for 
an underfeed oil system, and one is desired, drill a small 
hole through the bottom of the box and tap it for a small 
U-shaped pipe. The short leg of the U should then be 
screwed into the bottom casting and the long leg fitted 
with a sight feed or plain metal oil cup. Oil channels 
must then be cut in the bottom box the same as in the cap. 



CHAPTER XV. 

BELTING AND INSTALLING HOLDERS. 

Leather belting of good quality is undoubtedly the best 
for driving molder cutterheads. Light (22 or 24-oz.) two- 
ply belting is generally the correct selection for heavy-duty 
top and bottom head drives, but single-ply center stock is 
the logical choice for side head and all other drives on 
medium and small size machines. Next to leather is the 
four and five-ply woven canvas, impregnated with rubber or 
a similar substance. 

To drive a cutterhead effectively, the belt must be very 
flexible so it will wrap around the small pulleys to good 
advantage. It must have great strength and be able to 
stand up under continuous high-speed service. When tight- 
eners are brought to bear on belts to keep them at uniform 
tension, as they gradually become lengthened from con- 
tinued service, the belts should be made endless. Other- 
wise, the ends are usually Joined together with a tough wire 
lacing either hand or machine sewed. When cutting a new 
belt to net length, it is usually safe to allow about 1/10-in. 
to %-i^- to the lineal foot for stretch. In other words, cut 
it just that much shorter than the actual tape measurement 
around the pulleys. Cut the ends of the belt perfectly 
square with a try-square. For ordinary wire lacing, to be 
put in by hand, use a punch which cuts a hole slightly less 
than %-in. Punch a single row of holes 5/16-in. from the 
end and let the holes be about %-in. apart on center. Make 
an even number of holes in each end, if possible, so the 
belt can be sewed in such a manner as to equalize the side 
pull of cross-over strands at each side of the center, see 
Fig. 84. 

The method of sewing, shown in Fig. 84, is simple but 
effective and keeps the edges of the ends even. Always 



BELTING AND INSTALLING HOLDERS. 



143 



turn the grain or smooth side of a single-ply belt to the 
pulley and lace so that no cross-over strands show on the 
pulley side. Cut the wire about seven times longer than the 
width of the belt and start the two ends from the back 
side of the belt throught holes 1 and 1-A, respectively. Pull 




Fig. 84. Method of sewing- wire lace by hand. 

the ends evenly and draw them across the joint on the pul- 
ley side and thru holes 2 and 2-A, respectively, then thru 
1 and 1-A again, then cross the pulley side thru 2 and 2-A. 
One strand is then crossed over from 2 to 3 on the back 
and the other over to 3-A from 2-A. Continue until the 
edges of the belt are reached, and then cross the wire over 
to an adjacent hole or draw it thru an extra hole, as shown 
at 9, Fig. 84. After lacing, hammer the wire down flat. 
The belt is then ready for service. Put single belts on so 



144 MACHINE HOLDER PRACTICE. 

the point of the lap on the inside runs toward the pulleys, 
because the lap on the outside of a belt is most likely to 
come apart when the point is run against atmospheric pres- 
sure. Double belts should be put on so the points of the 
laps will run with the pulleys as both sides point in the 
same direction^ see Fig. 85. 

Belts should be kept clean and free from oil and grease. 
Mineral oils, in particular, rot leather rapidly. Where 
belting is liable to become oil soaked, mechanical means 
should be taken to keep the oil from the belt. Where this 
is impossible the belt should always be removed from time 
to time and all oil extracted by some solvent such as naptha 
or benzine. Packing the belt in dry sawdust, whiting, or 
some similar absorbent material will sometimes answer the 
purpose. If it is impossible to remove the belt, wiping it 
while on the pulley with a dry cloth or waste will help. An 
excess amount of oil on a belt gives a bad frictional sur- 
face and causes it to slip, and also has a tendency to injure 
the sticking qualities of the ordinary cements in belt laps. 

Should laps begin to open up on account of the presence 
of oil, it will be necessary to de-grease the parts to be joined 
and scrape off all old cement, or the new cement will not 
stick satisfactory. Do not think that you can remedy the 
trouble by riveting or driving tacks or belt fasteners 
through the joint. This simply makes a bad situation 
worse, for the leather will probably break where the metal 
pierces it. There is a right and a wrong way to repair 
laps, as well as to cement new laps, and the quickest and 
easiest way is not always the most economical in the end. 
It is easy to drive rivets or fasteners in a belt but it is 
just as well, before doing so, to think how much you 
weaken the belt at that point, how out of balance you make 
it, and consequently how it will jump every time the fast- 
eners go around the cutterhead pulley. The proper way 
is to clean the open laps and apply good cabinetmaker's 
glue or regular belt cement, rub out all surplus glue, and 



BELTING AND INSTALLING HOLDERS. 



145 



then put on the clamps or nail a piece of board over the 
joint and let it stand at least an hour before releasing the 
pressure. 

To make a new lap joint in a single-ply leather belt, 
square the ends and lay off the length of lap equal to about 
the width of the belt. Make the lap joint point the same 
way as other lap joints in the belt. Work each lap to a 
feather edge with a belt or spoke shave and scraper. Both 




PULLEY SIDE 



|*-EQUAL TO WIDTH->I 





Pig. 85. Showing- how the laps in single and double-ply belts 
should run. 

laps must be made square and even so the joint will be 
the same thickness as the rest of the belt. Rough the sur- 
face of each lap with a rasp or piece of coarse sandpaper 
to give the cement a better chance to stick. Clamp or 
nail the belt to a smooth board so that it will lay perfectly 
straight when the laps match one above the other. If the 
work is being done in a cold room, warm the board and 
belt laps before applying glue or cement. When belt cement 
is used, follow the directions accompanying it, but in using 
cabinetmaker's glue, brush it on both laps and rub it in, 
then fold laps together and rub the outside of the joint 
briskly with some blunt tool to drive out all air bubbles and 



146 MACHINE HOLDER PRACTICE. 

pockets. Then apply a flat even pressure by clamping or 
nailing a piece of board directly over the joint. Let stand 
over night, or half a day if possible, before releasing the 
pressure and putting the belt in service. 

Avoid putting belts on too tight. If a belt is put on 
and run too tight, it becomes overstrained and injured, 
excessive friction is produced in the bearings and there is 
danger of damaging the machine boxes. If the demands 
on a belt are unusually severe, owing to a regular line of 
heavy work, a "floating" tightener can be placed on the 
slack side near the drive pulley. A yielding tightener, de- 
riving its tension from its own weight or from coil springs, 
is a good thing, but when an unyielding tightener is used 
there is always a temptation on the part of the operator 
to screw it down too far and thereby make the belt al- 
together too tight. Lubricating oil, water, fine sawdust, 
and all general foreign substances should be kept off of 
cutterhead belts. Keep the belts clean but do not allow 
them to become dry and hard from want of proper lubri- 
cation. Leather belts in particular must be kept pliable 
and soft. An occasional but very light application of warm 
tallow, neatsfoot oil, or good belt dressing is just the thing 
to lubricate leather belts. The practice of doping a belt 
with rosin, soap, varnish, etc., to make it pull better is 
only a temporary relief and if continued to any extent 
vv^ill certainly ruin the best belt ever made. It is like dop- 
ing the human body or mind to produce greater activity. 
The effects of a treatment soon wear off, leaving one in 
worse condition than before. If the stimulation is con- 
tinued a collapse is inevitable. 

It is a good plan in factories and mills where fast-feed 
machines are kept in continuous service, to have duplicate 
machine belts cut to length and ready for instant replace- 
ment. Belts should be inspected regularly and given 
proper care and attention, rather than be allowed to run on 



BELTING AND INSTALLING MOLDERS. 147 

and on until they get in such a condition that some ex- 
treme action is necessary to save them from ruin. 

Never throw a cntterhead belt off or on the pulleys at 
full speed; roll it on by hand or throw it on at very slow 
speed. When a belt is thrown onto a pulley moving at high 
speed, one edge of the belt is given a terrific strain all in 
an instant, and as a result that edge is stretched more than 
than the other. Often the belt becomes permanently set 
in this unequally-stretched condition and runs crooked ever 
after. Instead of traveling straight, the crooked belt oc- 
cilates across the faces of the pulleys and is likely to set 
up end play in the cutterhead spindles. 

A belt should be about 1-in. narrower than the pulleys 
over which it travels. If it does not seem wide enough to 
deliver the power required, put on a wider belt and use 
voider pulleys. A means sometimes employed to prevent 
slippage is to cover the pulley faces v^ith leather. It is 
claimed that leather-covered pulleys will enable belting to 
transmit 25 per cent, more power than pulleys having a 
smooth iron surface. In preparing a pulley for a leather 
covering, begin by cleaning the surface thoroughly with 
naptha or benzine, then wipe it dry and warm it slightly. 
If possible^, make the covering endless and about %-in. to 
the foot shorter than the circumferance of the pulley. Place 
the endless cover on the pulley, pushing, it on about 1-in. 
or more, then brush cement on the exposed inside surface 
of the cover and the exposed outside surface of the pulley, 
being sure that the cement is of the right consistency. Eub 
it thoroly into the leather and onto the pulley. Then 
take the pulley by its spokes and drive the cover on by 
striking it on the floor or bench. Do this quickly, but care- 
fully, for if you strike too hard, or on one side more than 
the other, you may bend the leather so that it will be im- 
possible to drive it onto the pulley. If it sticks a little, 
pry it loose with a screw-driver, then force it down, using 
the screwdriver as a lever. When the cover is completely 



148 MACltlNJE MOLDER Pl^ACTlCE. 

on, rub the edges with some blunt tool to make good contact 
and work out surplus cement and any air pockets. A few 
livets are generally added as a matter of safety. 

To find the surface speed of a belt, multiply the diam- 
eter of a pulley over which it runs by 3.1416 or 3 1/7, and 
this product by the r.p.m. of said pulley. The surface 
speed of a belt should never exceed 5,000-ft. per minute. 
The speed of pulleys or any rotating parts can be easily 
and quickly figured if one remembers this simple fact: 
That the speed of the driving pulley in r.p.m. times its 
diameter equals the speed of the driven pulley in r.p.m. 
times its (the driven pulley) diameter. Example: 

Speed of lineshaft 300 r.p.m. 

Diameter of lineshaft pulley . . . 30-in. 
Diameter of driven pulley. . . . 10-in. 
Speed of driven pulley N 

300 X 30 = 10 X N 
9000 = 10 X jST 
9000 

= N or 900 

10 

300 X 30 = 10 X 900 

Note: N represents unknown quantity. 

A single-ply leather belt, 1-in. wide, running 800-ft. per minute 
will transmit 1 h. p. and for other thicknesses- figure the unit speed 
as 500, 40*0, and 300, respectively, for two-ply, three-ply and four- 
ply. Remember, the greater the speed of the belt, the more horse 
power transmitted in direct proportion, but do not let the speed 
exceed a mile a minute. 

To figure the length of belt for a drive when it is incon- 
venient to measure the distance with a tape line: Add the 
diameter of the two pulleys, multiply this result by 3.1416, 
and divide by 2. To this quotient, add twice the dis- 
tance between centers of shafts and this will give the re- 
quired' length provided both pulleys are about the same 
size. When one pulley is considerably larger than the 



BELTmG AND INSTALLING MOLDERS. 149 

other, square the distance between the centers of the shafts ; 
add to this the square of the difference between the radii of 
the two pulleys ; from this total extract the square root and 
multiply by two. Call the total thus obtained, T. Then 
add the diameters of the two pulleys together, multiply 
result by 3.1416 and to one-half of this add the amount 
Just designated as T, and you will have the length of belt 
required. To find the number of lineal feet in a roll of 
belting of any kind or ply, add the diameter of the roll 
in inches to the diameter of the center hole, multiply by 
the number of coils, counting from the center to the out- 
side, and multiply this product by .1309. 

SETTING A HOLDER. 

A molder, like an engine or other important piece of 
machinery, should set level and be firmly bolted down to a 
solid floor or foundation. Concrete foundations are good 
and unless there is a good concrete or heavy plank and 
timber floor, a special foundation should be prepared. The 
conventional method of bolting a machine to a plank floor 
or timber foundation is to use lag screws and washers. 
Lag screws are also used to anchor machine bases on con- 
crete floors and foundations. Holes are cut in the concrete 
to correspond, in position, to holes in the machine base. 
The machine is then positioned over the holes, lined up 
with the driving shaft, if belt drive is to be used, and 
leveled with hardwood shims so all feet rest firmly on the 
foundation. Small channels are then cut to each hole in 
the concrete and when the lag screws are hung in place 
in the machine-base holes, melted babbitt or lead is poured 
in around them. This anchors the machine very substan- 
tially. 

Common sulphur is sometimes used in the place of bab- 
bitt metal because of its comparative cheapness. When sul- 
phur is used, no channels need be cut for pouring because 
the melted sulphur can be poured directly into the holes 



150 MACHINE HOLDER PRACTICE. 

and the lag screws set in immediately after. This is possible 
because sulphur cools more slowly than metal. Of course, 
the lag screw is not pushed all the way down in the cool- 
ing sulphur, but within about %-in. or 1-in. of its limit, 
and turned the balance of the distance with a wrench. 
When the sulphur hardens it holds the lag screws firmly 
in place. 

Another method of fastening machines to concrete foun- 
dations is to put down inverted anchor bolts with large 
washers (washers which prevent bolts from turning) and 
fill in around these bolts with cement, sulphur, or melted 
metal. The machine base is then set down over the pro- 
jecting ends of these bolts and fastened down with nuts 
and washers. 

If a molder is to be driven by an individual motor, the 
usual practice is to connect the motor directly to the ma- 
chine countershaft by a flexible coupling. A flexible coup- 
ling is preferred to a solid coupling for several reasons; 
it relieves the motor of certain mechanical jarring and aids 
it in getting under way to better advantage when started; 
also permits of a slight misalignment in the shafts without 
causing the usual trouble incident to using solid couplings. 

The size motor required to drive any particular size 
molder depends largely upon the kind of service the ma- 
chine is to be put to, whether light, medium, or heavy use, 
intermittent or continuous, slow-feed or fast-feed service, 
etc. The following table shews pretty nearly the size 
motors required for various molders operated under aver- 
age conditions. 

Size of the Lig-ht and 

Molder Medium Service 

6-in. 5 h.p. motor 

8-in. 71/2 h.p. motor 

10-in. 10 h.p. motor 

12-in. 15 h.p. motor 

15-in. 20 h.p. motor 

18-in. 20 h.p. motor 



Heavy Service, 


Past 




Feeds, or Both 


n/2 


to 


10 


h.p. 


motor 


10 


to 


15 


h.p. 


motor 


15 


to 


20 


h.p. 


motor 


20 


to 


30 


h.p. 


motor 


25 


to 


30 h.p. 


motor 


25 


to 


35 


h.p. 


motor 



CHAPTEE XYI. 

MOLDING SHAPES. 



REVERSE OGEE PGEE 



ROUND EDGE (R.E.) BEAD 



OVOLO 



GROOVE 



FLUTE 



T 




COVE 



COVE AND BEAD BEAD AND COVE RABBETT 



BEVEL 




MITER 



ROUND QUARTER ROUND 9i ROUND 




ROPE MOLDING 



AND DART 
BOSSED) 



Names of a few common molding shapes. 



152 



MACHINE HOLDER PEACTICE. 




PARTITION CAP 



PICTURE MOLDING 





PICTURE FRAME 
MOLDING 



PARTITION SHOE 



DOOR SADDLE 



WINDOW APRON 



G=CJ^ 




CASKET BAND OR ELECTRICAL MOLDING 
LEDGE (FOR WIRES) 

MOLDING 




WATER TABLE OR DRIP CAP 



RABBETTED DOOR JAM 

[r~\ 




PEW BACK RAIL 



BRICK MOLDING 



RABBETTED 

WAINSCOT CAP 



Showing one style each of several different kinds of mold- 
ing commonly used in the building trades and casket manu- 
facturing. 



MOLDING SHAPES. 



153 





- CASKET BASE 
(TWO MEMBER) 



DOOR AND WINDOW STOP 



^ V 

CHANEL CASING 



BACK BAND 



A 



THRESHOLD 



CASING BACKED OUT ON BOTTOM TO FIT ROUGH WALLS 



1_J 



WINDOW JAMB OR. PULLEY STILE 




CASKET LID OR 
CAP MOLDING 



n 




WINDOW SILL 



154 



MACHINE HOLDER PRACTICE. 




PAIR OF ASTRAGALS 
FOR SLIDING DOORS 



PLATE RAIL 
(TWO MEMBER) 




ASTRAGAL FOR 
SWINGING DOORS 



OGEE SOLID WOOD GUTTER 



MOLDING SHAPES. 



155 



.1 


j' V V V 


^e ^ 


BEADED CEILING 


V CEILING 


I^V V V 


^<IZI3 


DOUBLE BEADED CEILING 


DOUBLE V CEILING 


TWO LAP RUSTIC OR 


NOVELTY SIDING. 


<~Z^^^' .^1 


BOSTON CEILING 


FLOORING 


/ ?\ ' ' H 


V RUSTIC 


CHANNEL RUSTIC SIDING 1 


z^^-—?^^-- ^ 


DOUBLE V RUSTIC 


DROP SIDING 


^"""^ P 


ANGLE RUSTIC 


NOVELTY 



The above patterns are generally run on fast-feed molders 
or matchers, the V's, beads and bevels being- worked with pro- 
file discs mounted on the profile spindle. They can also be 
made with ordinary knives on four-side, square-head molders. 



156 



MACHINE MOLDEE PRACTICE. 



jm^ 


LZTittEtf 


^nHMK 


■Sfl^^^B* 


^^, ^I^^H^^^H^^^^^^^^^^^^Rl 




SHll>:^^ ll^H^I^IK 


-"^w 



MACHINE HOLDER PRACTICE. 



157 



\ \ r 










INDEX TO ILLUSTEATIONS. 



CHAPTER 1. 

Typical outside molder 8 

An inside molder 11 

Fig. 1. Plan and side-view of molder in proper align- 
ment 10 

A square slotted cutterhead fitted with ordinary straight 
surfacing knives 14 

CHAPTER II. 

Fig. 2. Solid and sectional knives 16 

Fig. 3. Patterns with thin edges worked with top head 17 
Fig. 4. Showing how sectional cutters should be ar- 
ranged 19 

Fig. 5. A few diflferent types of knives 21 

CHAPTER III. 

Fig. 6. Balancing knives set in staggered fashion 24 

Thin high-speed steel knives attached to square head, 
with caps and bolts 26 

CHAPTER IV. 
Fig. 7. How to use the molder or "stickerman's" rule.. 29 
Fig. 8. Another method of setting knives correctly 33 

CHAPTER V. 

Figs. 9, 10, 11, 12, 13, 14, 15. Moldings on which under- 
cutting is necessary Z7 

Fig. 16. Attachment for working Byrkit lath, at rear 
end of an inside molder 39 

A square self-centering side head fitted with thin knives 
and caps 54 



INDEX TO ILLUSTRATIONS. 159 

CHAPTER VI. 

Figs. 17 and 18. Making half-round bushings, for pulleys 42 

Fig. 19. Trough in which piano fall boards are run 43 

Fig. 20. Cross-section of a front fall board 44 

Fig. 21. Special machine for tapering and jointing col- 
umn staves in one operation. • • 46 

Fig. 22. One method of making plain tapered staves in 

one operation 47 

Fig. 23. Showing how staves for tapered columns are 

laid out 48 

Fig. 24. Stave in position alongside form 49 

Fig. 25. Method of laying out sprung crown molding 

for circular porches or lowers 50 

Fig. 26. Arrangement of guides for running circle work 52 

Fig. 27. Molding segment and circle work on edge 53 

CHAPTER VII. 

Figs. 28 and 29. Arrangement of knives and guides for 
running molding face down 56 

CHAPTER VIII. 

Fig. 30. Three methods of fitting up knives for planing 

without tearing cross-grain 60 

Fig. 31. Another way to fit up surfacing knives for 

working cross-grain 61 

Figs. 32 and 33. Methods of fitting up rabbetting knives 

to make non-tearing cut 62 

Figs. 34 and 35. Special knives for cutting the edge of 

rabbetts 63 

Fig. 36. Special grooving cutter 64 

Fig. 37. Reinforcing a wide knife 66 

Fig. 38. Four different kinds of side braces 67 

Fig. 39. Two ways to brace extra long knives 68 

Fig. 40. Four types of "scoop" knives for making gutter 69 

Fig. 41. Bracing a loop knife with T-bolt and steel block 70 
Fig. 42. Another method of clamping loop knives to a 

square cutterhead 71 



160 MACHINE HOLDER PRACTICE. 

Fig. 43. Making ogee gutter ,. 72 

Fig. 44. Special blocks for enlarging square heads IZ 

Fig. 45. Hooks in position to hold projecting ends of 

long knives 74 

CHAPTER X. 

Fig. 46. Making moldings in pairs, face down 76 

Fig. 47. Center guide in pressure bar 11 

Fig. 48. Picture frame moldings made in pairs, face up 78 

Fig. 49. Four types of practical splitting cutters 80 

Fig. 50. Special high-speed steel splitting cutter and 

holder 81 

Fig. 51. Saving an extra molding by under-cutting 82 

Fig. 52. Combination head for splitting and planing.. 83 
Fig. 53. One method of making screen door stock and 

saving the molding. Fig. 54. Machine set up for 

making molding in Fig. 53 84 

Gang of splitting saws mounted on self-centering sleeve 

for use on molder spindle 85 

CHAPTER XI. 

Fig. 55. Divided rip saw for use on top or bottom 
spindles 86 

Fig. 56. Position of top rolls for feeding special casket 
sides 87 

Fig. 57. Line-up of guide rail and inside head for mak- 
ing slack-center glue joints 88 

Fig. 58. Method of making stair rail in two runs 90 

Fig. 59. vSpecial head rabbetted to receive formed lips.. 92 

CHAPTER Xn. 

An outside, four-head, fast-feed molder 94 

One type of six-knife, slip-on round head for top or 

bottom spindle of molder 95 

Self-centering "vise-grip" profile head 96 

Two universal chamfer heads 97 

A fast-feed molder with hopper feed 98 



INDEX TO ILLUSTRATIONS. 161 

A three-disc, combination head for grooving- heavy 

planks, etc , 99 

Special combination head used by N. C. R. Co 101 

A five-head molder ..... ; . . . 102 

Profile header head fitted with high-speed steel, formed 

knives , 103 

A g-roove head for flooring 104 

Fig. 60. Transverse T-slot head carrying formed knives 

for multiple work 105 

Fig. 61. Knife setting jig for round heads 106 

Fig. 62. Radial gage for setting knives 107 

Fig. 63. A stand for setting and balancing irregular 

cutters 108 

Fig. 64. Jointing straight thin steel knives on a round 

head 109 

Fig. 65. Jointing thick knives on square head 110 

Grinding straight knives with portable grinder Ill 

Fig. 66. One type of side head truing device in posi- 
tion 112 

Fig. (yJ . Formed stone and holder for jointing irregu- 
lar knives on top or bottom head 113 

Fig. 68. ' Another type of side-head jointer and special 
four-wing, fast-feed head fitted with self-centering 
sleeve and thick high-speed steel cutters 114 

Fig. 69. Side head jointing attachment in position for 
jointing the formed cutters of a matcher head 115 

Fig. 70. Showing one type of jointing device attached 
to slide bar on a jointing and setting stand 116 

A two-disc combination of self-centering clamp sleeve. . 117 

One type of pedestal head grinder 118 

A six-head, fast-feed, inside molder 120 

Inserted tooth rip saw with clamp collar and self-cen- 
tering sleeve 121 

CHAPTER XIII. 

Figs. 71 and 72. Two different methods of making rab- 
betted molding 124 



162 MACHINE MOLDEK PRACTICE. 

Figs. 1Z, 74, 75. Showing how cutting angle changes 

with depth of cut, and how to lay out molder scale.. 126 
Fig. 76. Laying out knife profile with drawing instru- 
ments 129 

Fig. 77. Layout of knife to cut a perfect miter 130 

Fig. 78. Laying out quarter-round knives 132 

Figs. 79, 80, 81. How to cut, spread and twist spike 

knives 134 

A three-disc side head tipped to show self-centering 
sleeve 135 

CHAPTER XIV. 

Fig. 82. Showing lower half of cutterhead box prepared 

for babbitting 137 

Fig. 83. Proper location of oil channels 139 

A handy babbitt scraper 140 

CHAPTER XV. 

Fig. 84. Method of sewing belt with wire lace 143 

Fig. 85. Showing how laps in single and double-ply 
belts should run 145 

CHAPTER XVL 

Molding shapes and patterns 151, 152, 153, 154, 155 

A general purpose outside molder built to take slip-on 

heads 156 

An all motor-driven, ball-bearing molder 157 



MACHIN^E HOLDER PRACTICE. 163 



REPRESENTATIVE TYPES 

OF MODERN 

MOLDING MACHINES 

D n 

D 



164 



MACHINE MOLDER PRACTICE. 



o 

fcuD 
C 



PQ 






MACHINE MOLDER PRACTICE. 165 



PATENTED 



MOULDER 

COMPLETELY MOTOR DRIVEN 

SPECIFICATIONS 

SIX-INCH MOULDER. 

Diameter of Spindles, where heads slip on 1-13/16-in. 

Diameter of Cutter Heads 4 to 7-in. 

Type of Cutter Heads Sl:p-on, Round or Square 

Spindle Speeds 3,450 to 3,600-r.p.m. 

Vertical Spindles (length for head) 4-in. 

Vertical Spindles, maximum angle 45-deg". 

Number of Feed Speeds 4 

Standard Feeds 25 to 100-f t. per min. 

Diameter of Feed Rolls ,. 8-in. 

Width of Stock 00 to 6-in. 

Thickness of Stock GO to 4-in. 

Current 110, 220. 440, 550 Volt, 2 or 3 Phase, 60 Cycles 

Table Heig-ht 34-in. 

Leng-th over all 88-in. 

Width over all 46-in. 

Approximate Weight 6,80i0-lbs. 

TWELVE-INCH MOULDER. 

Diameter of Spindles, where heads slip on 1-13/16-in. 

Diameter of Cutter Heads 4 to 7-in. 

Type of Cutter Heads Slip-on, Round or Square 

Spindle Speeds 3,450 to 3,600-r.p.m. 

Vertical Spindles (leng-th for head) 4-in. 

Vertical Spindles, maximum angle 45-deg'. 

Number of Feed Speeds 4 

Standard Feeds 25 to 100-f t. per min. 

Diameter of Feed Rolls 8-in. 

Width of Stock 00 to 12-in 

Thickness of Stock 00 to 4-in. 

Current 110, 220. 440, 550 Volt, 2 or 3 Phase, 60' Cycles 

Table Height 34-in. 

Length over all 96-in. 

Width over all 48-in. 

Approximate Weight 8,000-lbs. 

EXTRA ATTACHMENTS. 

Hopper Feed Attachment to Take 3 or 6-ft. Lengths 

Jointers for Top, Bottom and Side Heads. 
Knife Grinder, motor driven. 
Shaving Hoods. 

VONNEGUT MACHINERY COMPANY 

INDIANAPOLIS, U. S. A. 



166 



MACHINE HOLDER PRACTICE. 




rO 



MACHINE HOLDER PRACTICE. 167 

The Mattison 

Motor Driven 
Ball Bearing 
Heavy Duty 

Moulder 



Made in 4, 6, 8, 10 and 
12-in. Sizes 



Manufactured by 

MATTISON MACHINE WORKS 

Main Office and Works 
ROCKFORD, ILLINOIS 



168 



MACHINE MOLDER PRACTICE. 




MACHINE HOLDER PRACTICE. 169 



HERMANCE MOLDERS 

Equipped either for general 
purpose or fast-feed work. 



Hermance No. 40 — 12 and 16-inch. 

A heavy molder that combines the desirable 
features of both the inside and outside types. No 
belts on working side allows free access for quick 
adjustments and easy set-ups. Has the massive 
frame, rigid bed and heavy bearings on both sides of 
top and bottom cutterheads and feed rolls that are 
the desirable features of the true inside molder. 
Hopper feed if desired. 

Hermance No. 50 — 8, 10- and 12-inch. 

Noted for remarkable ease and speed with which 
set-ups may be made, due to its accessibility and 
the simplicity and completeness of adjustment 
features, making it an exceptional machine for 
general^purpose work. May be equipped with 
our fast-feed features, which are of unusual sim- 
plicity. 

Hermance 6-inch — one, two, three or four sided. 

An ideal machine for accurate working of small 
moldings. 

Write for catalog illustrating and fully des- 
cribing our line of modern molders and other 
high-grade wood-working machinery. 

HERMANCE MACHINE CO. 

Williamsport, Pa. 



170 



MACHINE MOLDER PRACTICE. 







^ 



^ 



MACHINE MOLDER PRACTICE. 171 

WOODS No. 419 SUPER-SIX 
MOULDER 

THE ONLY MACHINE OF ITS KIND IN 

THE WORLD FOR WORKING THE 

LARGEST AND THE HEAVIEST 

MOULDINGS ACCURATELY 

AT FAST FEEDS 



The most complete line of 
moulders manufactured are 
made by The S. A. Woods 
Machine Co., Boston, U.S. A., 
builders of wood-working 
machinery since 1854. 

If you own or operate a 
moulder, ask us to place your 
name on our mailing list to 
receive our moulding publica- 
tions which we issue from 
time to time. 

To keep in close touch 
with this progressive manu- 
facturer of fast-feed moulders 
will make YOU a dominant 
factor in the manufacture of 
mouldings. 

S. A. WOODS MACHINE COMPANY 

BOSTON, U. S. A. 



172 MACHINE MOLDER PRACTICE. 




Woods "Sawco" Electric Hand Grinder. 




The Woods "Sawco" Electric Hand Grinder in Operation. 



MACHI^'E MOLDER PRACTICE. 173 

WOODS "SAWCO" ELECTRIC 
HAND GRINDER 

ONE OF WOODS LABOR AND 
TIME-SAVING DEVICES 



Adapted Especially for Moulding- Machine Knives 



On fast-feed work, where formed knives are 
used, this grinder is indispensable. It will elimi- 
nate almost 50% of the time lost in taking care of 
the cutters. After a formed cutter has been joint- 
ed several times, it becomes necessary to remove 
the cutter-head from the machine and take the 
cutters out and grind off the heel. This not only 
takes a great deal of time in itself, but means an 
equal loss of time in re-setting the knives in the 
head and getting the head back into the machine. 
In addition to this, more jointing is necessary be- 
fore the head can be put in operation with the 
consequent loss of time and expensive high-speed 
steel. The SAWCO grinder will eliminate all 
of this and the heel can be ground off of the 
knives without taking the knives out of the head 
or even removing the head from the machine or 
disturbing the set-up in any way. 

S. A. WOODS MACHINE COMPANY 

BOSTON, U. S. A. 
The History of the Moulder is the History of the S. A. Woods Machine Co. 



^u61 



LIBRARY OF CONGRESS 




017 180 540 5 



■■*% 












'.^';;^ 



'>;^V^' 



^»f>,'v 









